# Lifestyles & Discussion > Freedom Living >  1903 six HP steam engine powers modern off grid power system

## Anti Federalist

*I. Want. This.*

http://www.otherpower.com/steamengine.shtml

Steam Powered Battery Charger



2000 watts at 200 rpm!!!

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## noxagol

I will immediately call the authorities on this. How dare she produce electricity without the blessing of her governments! 

But yes, neat. I want to make a Sterling Engine, mounted to a heliostat, which I haven't been able to figure out how to build yet, with a parabolic mirror or frenel lens mounted to it and have a generator attached to it. Mount that whole deal to your roof.

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## acptulsa

> But yes, neat. I want to make a Sterling Engine, mounted to a heliostat, which I haven't been able to figure out how to build yet, with a parabolic mirror or frenel lens mounted to it and have a generator attached to it. Mount that whole deal to your roof.


Solar steam.  Love it!

Yeah, the perils of anachronistic technology.  So simple you don't need a team of engineers to run it.  How can we encourage the interdependence that makes tyranny possible if people have the knowledge and means to be self sufficient?  It's just terrible...

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## noxagol

Not even steam. A sterling engine runs on temperature difference. There is no fuel other than whatever provides heat, which in this case is the sun.

example of sterling engine : 



example of what i want to do: 



If you want steam engine, this is what you should go with imo based on my light research: http://www.greensteamengine.com/

I ran across this like two years ago and I can tell you the guy is making improvements. The Z style wasn't around back then. I would make a z 12 if ti were me and the pistons would be pretty big, cause I'm crazy like that. Power goes out, gas and water still work. Fire it up gas, boil some water, and power your neighborhood. Venturi burner works with no eletricity. Once you have power, you can switch to a forced air burner, or start with battery. Forced air burner is WAY better than venturi outside of needing power. 

The Z8 shown on the sight is a 30hp engine. Most homegenerators have a 6.5-13 hp engine which needs copious amounts of gas to run. And oil which must be changed every 100 hours or so. These green steams use the steam to lube and closed ball bearings. It really is an ingenious design. I'd like to see these made as internal combustion engines as well.

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## Anti Federalist

steam bump

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## noxagol

I'm thinking I might try to make a steam engine now.

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## pcosmar

I find that "Z drive" really interesting. I would like to see some data on wear and life expectancy under load. (real world).
Seems that may be the weak part of a very good design.

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## Acala

Is anyone selling small (5-20 hp) steam engines/boilers?  There are some enormous advantages to using steam to generate electricity - availability of fuel being among them.

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## YumYum

> Is anyone selling small (5-20 hp) steam engines/boilers?  There are some enormous advantages to using steam to generate electricity - availability of fuel being among them.


I talked to this man. Check this out.

http://home.earthlink.net/~dlaw70/12stmng.htm

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## Anti Federalist



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## Acala

> I talked to this man. Check this out.
> 
> http://home.earthlink.net/~dlaw70/12stmng.htm


3 hp is a bit too small.  You need about 2 hp per kilowatt.  And muy costoso!  I think a used engine would be better.  Lots of them went into the iron scrap drive during WWII, but there should be plenty left.

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## Anti Federalist

> 3 hp is a bit too small.  You need about 2 hp per kilowatt.  And muy costoso!  I think a used engine would be better.  Lots of them went into the iron scrap drive during WWII, but there should be plenty left.


Believe it or not, they can found out in the woods, at abandoned mill, mine and quarry sites, mostly.

And brought back to life!

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## Anti Federalist

Or convert gas four strokes:

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## pcosmar

Giving me ideas.
A dangerous thing indeed.

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## Acala

I'm in the midst of restoring an engine almost identical to this:

http://www.youtube.com/watch?v=EvWmQ...eature=related

I figure I can run it on ethanol or even wood gas if the gasoline becomes too expensive.

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## Anti Federalist

> I'm in the midst of restoring an engine almost identical to this:
> 
> http://www.youtube.com/watch?v=EvWmQ...eature=related
> 
> I figure I can run it on ethanol or even wood gas if the gasoline becomes too expensive.


Awesome, the old "make and break" engines are almost as neat as steam.

And IIRC, you run just about *any* volatile liquid fuel in them. 

Please post pic/videos when you get it up and running.

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## Ninja Homer



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## buenijo

OK, I'm gonna try to get this thread flowing. I've been doing a lot of research into small scale steam power in my spare time over the last several years. I am convinced that it's viable. However, the big problem is practicality. 

For anyone who is considering building a small scale steam power plant for home power, I recommend that you adopt several design criteria that are rooted in the principle of making the most of steam power's inherent strengths, and minimizing the effects of its weaknesses. The strengths include: (1) clean combustion, (2) can be very quiet if properly designed, (3) multi-fuel capacity, (4) long life. Weaknesses include (1) low thermal efficiency, (2) expensive unconventional components, (3) potentially dangerous. 

In my opinion, a small scale steam power plant for powering a small off grid home should adopt the following:

1. Use a piston engine, and a monotube steam generator. At low power levels suitable for powering a home a piston engine will be more efficient than a turbine. A monotube steam generator (as opposed to a boiler) is both the safest and most efficient option.
2. Operate the system at a constant low power (one the order of 1 KW or less) for long periods. This makes for a simpler system, but it also makes for a smaller system. Use the engine to drive a small efficient permanent magnet alternator for battery charging. Use an inverter on the battery to provide electricity, or you could go with a DC system. 
3. Put the heat in the exhaust steam to work for you. If this energy is not put to use, then the net efficiency of the system will be too low to be practical. But if it is put to full use the system can be more efficient than any other option (even grid power). The latent heat in the steam exhaust can (a) provide space heating, (b) heat water (including pasteurization or distillation if desired), (c)  provide air conditioning with absorption/adsorption cooling, (d) dry food, (e) can food, and many other applications (drying clothes, drying wood fuel, etc). The largest electrical loads in the home are electric heating elements and air conditioning compressor motors. If these can be displaced, then there is little need for a high powered system. What IS desired is a system that operates reliably at a reasonably high efficiency for long periods at a low output, and is easy and inexpensive to repair.

This is just an intro to start a discussion. Please reply if you're interested in exploring this topic further. I honestly believe small scale steam power can make a comeback, and hopefully in a big way.

ADDENDUM: I suggested absorption/adsorption cooling as an option for cooling with heat. Other possibilities include steam jet cooling, refrigerant jet cooling, ammonia absorption, and various absorption cooling systems that operate at a high vacuum and use water as the refrigerant. Each have various advantages and disadvantages. I think there is the most promise with silica gel/water adsorption chiller systems that have recently become available in some markets in Europe. There is a lot of research into these systems going on today. Finally, if the efficiency of a small scale steam engine system can be sufficiently high, then a refrigerant compressor could be driven directly to support a ductless a/c unit. This would avoid the many energy conversion losses in generating electricity and using the electricity in small motors. However, the efficiency would have to go up many fold over traditional small steam units to make this a practical possibility.

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## Ninja Homer

A 9-foot parabolic dish plus a 6-inch Tesla turbine generates 18-20 kilowatts per day.

http://phoenixnavigation.com/ptbc/articles/ptbc45.htm

The parabolic dish is used to produce steam, the steam runs the Tesla turbine, the Tesla turbine runs an alternator to produce electricity.  It's a pretty brilliant concept.

There's a lot of information at the above link, but the navigation sucks.  Here's one table of contents (click the buttons on top to change years): http://phoenixnavigation.com/ptbc/ar...1_articles.htm
And here's another: http://phoenixnavigation.com/ptbc/toc.htm
They also have a workshop available, but I don't know anything about it: http://newturbine.phoenixnavigation.com/

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## buenijo

I honestly don't mean to be a killjoy here, but basic physics must be considered. Some simple calculations will show that this claim is false... or at least it is vague.  

A 9 foot parabolic dish has a surface area of about 64 square feet. This is about 6 square meters. According to the National Renewable Energy Laboratory of the U.S. DOE, the region in the U.S. with the greatest solar insolation sees at most 10 KWh of solar energy per square meter on average during each day. The average region will see far less during most of the year. 

So, a 9 foot parabolic dish of 6 square meters placed at the most favorable site in the U.S. will see an average of 60 KWh of solar energy per day. One KWh of energy is equal to about 3412 btu of heat energy. This equates to about 205,000 btu of heat each day (equal to the burning of about 1.7 gallons of gasoline). Assuming that all of this heat can be transferred to water to make steam (not gonna happen), and using this steam to operate a turbine at 12% thermal efficiency (which is unlikely), we can generate at most 7.2 KWh of electricity (assuming zero losses in power conversion and transmission, which is impossible). In reality, the amount of electricity generated under these conditions for end use will be far less. In other words, the "18-20 kilowatts per day" claim is just plain BS. A more realistic figure is 1-2 KWh electricity per day under these conditions.

Facts and reasoning along these lines have led me to conclude during the last few years that the best means for an individual to truly achieve energy self-reliance is through a small piston steam engine fueled by biomass using extensive cogeneration. Another candidate includes using wood gasification to power internal combustion engines, but this is best used where high power needs are necessary (such as a small community). Photovoltaics is getting much cheaper and the associated electronics are getting cheaper and more reliable, and these systems are more practical in most settings for electricity generation. However, if heat is the primary desired product (as in a cold climate), then wood is really the only viable fuel for genuine energy independence. A small steam engine or wood gas engine system is a viable alternative in this setting for their ability to provide electricity as well as the required heat from wood fuel.

Finally, anyone who wishes to go off grid must learn that it will be imperative to conserve energy. We take energy for granted in the U.S. When you start thinking seriously about going off grid, only then can you appreciate how much energy we waste in this country.

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## Bruno

Welcome to RPF, buenijo!

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## HazyHusky420

Tesla : CENSORED BY THE US GOVERNMENT

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## Bruno

^^^ Watching now, it's captivating.   Thank you for sharing this, and welcome to the forums!

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## HazyHusky420

If anyone needs to be informed about free energy it's libertarians, because for one they believe it should be legal and two many are stuck in the oil/coal/nuclear trap. Don't get me wrong, I know nuclear isn't as bad as many claim, in fact i'll take nuclear over coal any day, but nuclear is still dangerous and there's no reason it should exist when we already have free energy.

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## speciallyblend

any suggestions on my first project?? i want to convert or buy an already converted engine ??   


http://cgi.ebay.com/5HP-TECUMSEH-ENG...item3a61f29ff2

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## buenijo

Speciallyblend, if you intend to construct a steam system, then I highly recommend that you build the steam generator first. I have a lot of ideas here.

If you're interested only in a back up source for electrical power only and not something to get off grid permanently, then powering an internal combustion engine with a wood gasifier is probably a better option. 

As far as converting an internal combustion engine to steam, I recommend that you check out this site: http://lynxsteamengines.com/converting.cfm. However, note that generally it's not a good idea. Good results are unlikely. A better option is to install a steam cylinder on top of the gas engine piston and connect the steam piston rod to the gas engine piston, then remove the gas engine piston rings to lessen friction. The gas engine piston and cylinder will serve as the steam engine crosshead.

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## Ninja Homer

> I honestly don't mean to be a killjoy here, but basic physics must be considered. Some simple calculations will show that this claim is false... or at least it is vague.  
> 
> A 9 foot parabolic dish has a surface area of about 64 square feet. This is about 6 square meters. According to the National Renewable Energy Laboratory of the U.S. DOE, the region in the U.S. with the greatest solar incidence sees at most 10 KWh of solar energy per square meter on average during each day. The average region will see far less during most of the year. 
> 
> So, a 9 foot parabolic dish of 6 square meters placed at the most favorable site in the U.S. will see an average of 60 KWh of solar energy per day. One KWh of energy is equal to about 3412 btu of heat energy. This equates to about 205,000 btu of heat each day (equal to the burning of about 1.7 gallons of gasoline). Assuming that all of this heat can be transferred to water to make steam (not gonna happen), and using this steam to operate a turbine at 12% thermal efficiency (which is unlikely), we can generate at most 7.2 KWh of electricity (assuming zero losses in power conversion and transmission, which is impossible). In reality, the amount of electricity generated under these conditions for end use will be far less. In other words, the "18-20 kilowatts per day" claim is just plain BS. A more realistic figure is 1-2 KWh electricity per day under these conditions.
> 
> Facts and reasoning along these lines have led me to conclude during the last few years that the best means for an individual to truly achieve energy self-reliance is through a small piston steam engine fueled by biomass using extensive cogeneration. Another candidate includes using wood gasification to power internal combustion engines, but this is best used where high power needs are necessary (such as a small community). 
> 
> Finally, anyone who wishes to go off grid must learn that it will be imperative to conserve energy. We take energy for granted in the U.S. When you start thinking seriously about going off grid, only then can you appreciate how much energy we waste in this country.


You're confusing the efficiency of a bladed turbine with a Tesla Turbine.  A Tesla Turbine is much more efficient (and cheaper to build, quieter to run, and more durable) than either a bladed turbine or a piston steam engine. http://en.wikipedia.org/wiki/Tesla_turbine

However, they _were_ being a little overly optimistic in their numbers.  This was back in 2004 when they were still in their theoretical stage.  Their current build is a 7 inch Tesla Turbine generator that averages 1kW/hour, 10 hours/day in Michigan.  It uses a parabolic trough made from plywood and covered in reflective material.  An average home would probably need 2 of these to cover their electric needs, and if you do it right you could also use the heat to heat your home and water.  Once it's built, it's built... it will work a very long time with little maintenance.  They're also working on a biomass heater to run the same Tesla turbogenerator.

The reason the Tesla turbine never caught on at the time he invented it was that it was very hard to make to spec with the metallurgy and metal fabrication technology of the time.  Now it's simply a matter of having a metal shop laser cut it out of stock stainless steel.

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## speciallyblend

> Speciallyblend, if you intend to construct a steam system, then I highly recommend that you build the steam generator first. I have a lot of ideas here.
> 
> If you're interested only in a back up source for electrical power only and not something to get off grid permanently, then powering an internal combustion engine with a wood gasifier is probably a better option. 
> 
> As far as converting an internal combustion engine to steam, I recommend that you check out this site: http://lynxsteamengines.com/converting.cfm
> 
> I advise anyone that should they pursue a serious effort to get off grid using steam power, then they should prepare to spend on the order of $10,000 minimum. In addition to this will be required a lot of time for development. There are simply no turn key systems out there. If anyone is serious, then I can provide a lot of good ideas and resources that will be helpful on how to best proceed.


hi , i am very serious but for now will have to look at smaller back up system etc, since i don't have the $$$$ yet to pursue thetotal offgird system yet but look forward to reading the link you provided. thanks  . At the moment i am investing in a small solar back up system but all these plans are when i have available money to invest!

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## speciallyblend

> You're confusing the efficiency of a bladed turbine with a Tesla Turbine.  A Tesla Turbine is much more efficient (and cheaper to build, quieter to run, and more durable) than either a bladed turbine or a piston steam engine. http://en.wikipedia.org/wiki/Tesla_turbine
> 
> However, they _were_ being a little overly optimistic in their numbers.  This was back in 2004 when they were still in their theoretical stage.  Their current build is a 7 inch Tesla Turbine generator that averages 1kW/hour, 10 hours/day in Michigan.  It uses a parabolic trough made from plywood and covered in reflective material.  An average home would probably need 2 of these to cover their electric needs, and if you do it right you could also use the heat to heat your home and water.  Once it's built, it's built... it will work a very long time with little maintenance.  They're also working on a biomass heater to run the same Tesla turbogenerator.
> 
> The reason the Tesla turbine never caught on at the time he invented it was that it was very hard to make to spec with the metallurgy and metal fabrication technology of the time.  Now it's simply a matter of having a metal shop laser cut it out of stock stainless steel.


so build me a cheap one hehe ready to be a customer

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## buenijo

Ninja Homer, I am familiar with the Tesla turbine. If someone were to design and build a very small turbine suitable for powering a home, then the Tesla approach is probably a good idea simply because it is a simpler design. However, I simply do not expect a very small Tesla steam turbine to be more efficient than a good piston steam engine. I'm not saying it can't be, I argue only that it's a lot more difficult than you may believe. A very small steam turbine is going to have to have extremely precise machining, and operate at extremely high speeds to get the efficiency above a good piston engine (assuming the same steam source, and assuming low power). 

* Please provide a link to where I can view the specifications of their current set up.

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## buenijo

Speciallyblend, here are some more links that you should check out... 

Wood Gasification:

driveonwood.com

woodgas.com (lots a great books available)... make sure to check out the wood gas camp stove

http://www.gekgasifier.com/ (wood gas power plants available)

Steam Power:

Uniflowpower.com

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## Acala

I live in literally one of the sunniest places on earth and have a 2kw photovoltaic system up and running on my house.  So I am bullish on solar energy.  BUT it has some seroous drawbacks.  The biggest is that it will only produce power during the hours of peak daylight.  So how are you going to power your freezer, lights, ham radio, ac, furnace, whatever from late afternoon to mid-morning?  

Batteries suck for long-term off-grid purposes.  They are expensive, heavy, toxic, have a limited lifespan, and cannot be easily improvised.

I have given serious thought to the idea of storing solar energy and the options are not very good.  If you have lots of land with a significant elevation gradient, and plenty of water, you can set up a system that pumps water into a reservoir on the high end of the property using solar energy during the day and then at night drain the water back down to a lower reservoir through a turbine at night.  But I don't have much water.

You could also use solar to electolyse water, store the hydrogen, then burn it in an internal combustion engine to run a generator.  But there are so many steps in the process it becomes very inefficient.  And hydrogen is a bitch to work with. 

The best option I have come up with for sunny, dry climates is storing solar energy as thermal energy during the day and then extracting it at night with a heat engine.  For example, you could use solar energy to heat a very large concrete block, solar oven style, during the day and then use multiple Sterling engines to run off the heat contained in the block and turn a generator during the night.  This would be simple and efficient, but fixed in place, and lots of moving parts because of the multiple sterling engines.  And still impacted by cloudy days.

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## acptulsa

> And still impacted by cloudy days.


Excellent observations.  Rather than two solar plants, a wind plant would be the better companion to one solar installation.

Especially if you happen to live near the Capitol.

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## buenijo

Acala, I suppose a battery bank is acceptable for low power loads (everything except large motors and electric heating elements). 

For refrigeration I recommend a combination of (1) excellent insulation, and (2) temperature moderation using water storage. A freezer can be superinsulated, and containers of water can be stored within. A good trick is to use salt water or water/glycol in the containers that will lower its freezing point. Likewise, a refrigerator can be loaded with water containers placed at the coldest point in the fridge with similar results (lower the thermostat setting for better results). 

Residential solar powered adsorption chillers have been developed recently. Unfortunately they are currently available only in Europe, but it's just a matter of time before we see them in the U.S. See www.sortech.de for a description of the units. These are powered by solar heated water. I say use the system to cool a large store of water during the day that can be drawn upon during the evening hours. The store of water could be heated during the day if it were necessary to provide space heating during the evening hours. This would take a lot of water on the order of 1000 gallons to be effective (assuming a moderately sized well insulated home). But a cylindrical tank 6 feet in diameter and 5 feet tall is enough... that's not so bad.

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## buenijo

HazyHusky420, I agree that nuclear isn't so bad. But I think coal is getting a bad rap too. In my opinion, as long as the coal is fully combusted with any heavy metals or other contaminants in the fuel scrubbed, then coal is a great option. BTW, the U.S. has about 1/3 of all known high grade coal deposits in the world (the U.S. is to coal as Saudi Arabia is to oil). 

Please note that (so far) I am convinced that the "global warming"/"climate change" argument is a load of BS.

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## osan

> Facts and reasoning along these lines have led me to conclude during the last few years that the best means for an individual to truly achieve energy self-reliance is through a small piston steam engine fueled by biomass using extensive cogeneration. Another candidate includes using wood gasification to power internal combustion engines, but this is best used where high power needs are necessary (such as a small community).


Fully agree.  I am now considering designs for a radial steam engine - 6 to 9 cylinders.  I also suspect that low pressure, high volume, low speed, low stress is the way to go for reliability and longevity.  Highly stressed designs using highly engineered materials are great until they break and there are no parts available to replace them.  That is when the virues of simplicity and low stress design become apparent... shortly before you freeze to death.




> Finally, anyone who wishes to go off grid must learn that it will be imperative to conserve energy. We take energy for granted in the U.S. When you start thinking seriously about going off grid, only then can you appreciate how much energy we waste in this country.


You are so on the money here.  Welcome to the forums.

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## osan

> If you want steam engine, this is what you should go with imo based on my light research: http://www.greensteamengine.com/


What happened to the site?  It's gone... perhaps a transient absence?  Anyone else?

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## noxagol

Not working for me either. Interesting.

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## Bman

> HazyHusky420, I agree that nuclear isn't so bad. But I think coal is getting a bad rap too. In my opinion, as long as the coal is fully combusted with any heavy metals or other contaminants in the fuel scrubbed, then coal is a great option. BTW, the U.S. has about 1/3 of all known high grade coal deposits in the world (the U.S. is to coal as Saudi Arabia is to oil). 
> 
> Please note that (so far) I am convinced that the "global warming"/"climate change" argument is load of BS.


I grew up 15 minutes from one of the largest anthracite deposits in the U.S.  There's a rail bed that runs right along it.  Probably hasn't had tracks for the past century, but that rail bed is kept pristine.

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## noxagol

Anthracite is awesome stuff.

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## Acala

> Excellent observations.  Rather than two solar plants, a wind plant would be the better companion to one solar installation.
> 
> Especially if you happen to live near the Capitol.


Unfortunately, while my home is in one of the sunniest places on the planet, it is also one of the LEAST windy places on the planet.

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## Acala

> Acala, I suppose a battery bank is acceptable for low power loads (everything except large motors and electric heating elements). 
> 
> For refrigeration I recommend a combination of (1) excellent insulation, and (2) temperature moderation using water storage. A freezer can be superinsulated, and containers of water can be stored within. A good trick is to use salt water in the containers that will lower its freezing point. Likewise, a refrigerator can be loaded with water containers placed at the coldest point in the fridge with similar results (lower the thermostat setting for better results). 
> 
> Residential solar powered adsorption chillers have been developed recently. Ufortunately they are currently available only in Europe, but it's just a matter of time before we see them in the U.S. See www.sortech.de for a description of the units. These are powered by solar heated water. I say use the system to cool a large store of water during the day that can be drawn upon during the evening hours. The store of water could be heated during the day if it were necessary to provide space heating during the evening hours. This would take a lot of water on the order of 1000 gallons to be effective (assuming a moderately sized well insulated home). But a cylindrical tank 6 feet in diameter and 5 feet tall is enough... that's not so bad.


Batteries are fine - until they wear out.  Might be very difficult to replace in a truly ugly situation.  But, now that I think about it, maybe a worn out lead/acid battery can actually be regenerated?  Anyone know why a lead/acid battery ultimately won't hold a charge?  Maybe time for me to do some research . . .

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## noxagol

A lead acid batter consists of lead and sulfuric acid. A battery works by moving a charge against current, a battery uses metal-acid reaction to do this. When you charge a battery, you reverse the process, but the lead is not restored 100%. The structure is left deteriorated in a tiny way and this builds up over time until the point that the structure of lead won't support the reaction effectively enough. Nickel-metal hydride batteries and lithium ion batteries and the newer lithium polymer batteries over come this to a great extent. 

At least, that's how I remember understanding it when I read about it.

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## Anti Federalist

> Batteries are fine - until they wear out.  Might be very difficult to replace in a truly ugly situation.  But, now that I think about it, maybe a worn out lead/acid battery can actually be regenerated?  Anyone know why a lead/acid battery ultimately won't hold a charge?  Maybe time for me to do some research . . .


Sulfation of the plates.

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## Ninja Homer

> Batteries are fine - until they wear out.  Might be very difficult to replace in a truly ugly situation.  But, now that I think about it, maybe a worn out lead/acid battery can actually be regenerated?  Anyone know why a lead/acid battery ultimately won't hold a charge?  Maybe time for me to do some research . . .


Radiant chargers are now out that can knock the sulfate off the plates.  Tesla technology brought back by John Bedini.  Radiant energy pulses can restore old, even dead batteries.  They charge batteries using less power than a traditional charger.
http://www.energenx.com/
http://www.r-charge.com/
It's pretty easy to find dead batteries.  If 75% of them can be restored to new condition one of these chargers could be pretty useful.

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## speciallyblend

> Radiant chargers are now out that can knock the sulfate off the plates.  Tesla technology brought back by John Bedini.  Radiant energy pulses can restore old, even dead batteries.  They charge batteries using less power than a traditional charger.
> http://www.energenx.com/
> http://www.r-charge.com/
> It's pretty easy to find dead batteries.  If 75% of them can be restored to new condition one of these chargers could be pretty useful.


  hmmm interesting, so i guess the charger cannot be cheap! Whenever i see a website that doesn't want to show a price i think hmmm cannot be cheap?  did you see a price on this charger??

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## osan

> A Tesla Turbine is much more efficient (and cheaper to build, quieter to run, and more durable) than either a bladed turbine or a piston steam engine. http://en.wikipedia.org/wiki/Tesla_turbine


Steam is great in many ways, but unless you have a vast, inexpensive, and clean energy source, it has a lot of problems.  That aside, Tesla turbines are indeed as good as it currently gets in that arena.  Their largest drawback lies in that their torque comes on only with very high spindle speeds, usually in the tens of thousands of RPM, which renders them poor candidates for low-tech materials and production means.  At such angular velocities, dynamic balance of the rotating mass becomes an issue, as does bearing and lubrication design.  Another issue lies with getting them so spool up, with which they typically need some help.  I have designed a simple solution for this.  At one end of the turbine we mount an impulse turbine that connects to the Tesla gang either directly, in which it goes along for the ride as the arrangement runs, or by a sprague clutch that will allow the impulse element to idle once power to it is removed.  A computer controlled or manually switched steam jet is used to start the impulse section, which has far better low speed torque characteristics than the Tesla section.  Once the team is up to speed, the power is cut to the impulse section, causing the sprague clutch to disengage, thereby allowing the section come to idle as the Tesla section operates.

Were I a billionaire entrepreneur looking to research coolness, I would be hard at work on high temperature super conductors.  If ever we develop such conductors that would operate up to, say, 150*F, the world as we know it would disappear in a couple of decades.  The implications of HTS materials would be quite literally staggering - they would change everything.  Imagine electrically powered commercial jet aircraft... or just go with anti-grav.

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## buenijo

> Fully agree.  I am now considering designs for a radial steam engine - 6 to 9 cylinders.  I also suspect that low pressure, high volume, low speed, low stress is the way to go for reliability and longevity.  Highly stressed designs using highly engineered materials are great until they break and there are no parts available to replace them.  That is when the virues of simplicity and low stress design become apparent... shortly before you freeze to death.


I agree. But I do emphasize that lower speeds is more important for longevity and reliability as compared to lowering pressures. I have designed (not yet built) a very simple steam engine, biomass furnace, and steam generator that uses existing mass produced components throughout. The pressure is fairly high, but kept under 300 psig. The engine speed is kept low. Contact me if you want specifics. I am interested to know your ideas as well.

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## Anti Federalist

A maker of "workhorse" stationary steam engines, from 2 to 18 HP, from, what appears to be, a back alley foundry in India.

Not the highest of quality, according to this blog: http://www.loligo.com/blog/?p=50

But fully functional. Waiting to see if my youtube messages elicit a reply since there was no contact info to be found.

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## buenijo

Very interesting and informative videos on small scale steam power:



















http://vimeo.com/15334957
http://vimeo.com/15167957
http://vimeo.com/15196290

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## Ninja Homer

> hmmm interesting, so i guess the charger cannot be cheap! Whenever i see a website that doesn't want to show a price i think hmmm cannot be cheap?  did you see a price on this charger??


The 2nd one has prices: http://www.r-charge.com/
Online ordering and everything.  I don't know, they may even be 2 sides to the same company, with the first geared towards industries and the second towards consumers.

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## Anti Federalist

WHOO HOO, update on the blue stationary steam engines pictured above.

Found the manufacturer:

http://www.tinytechindia.com/steampowerplan.htm

And here:

http://www.internationalsteam.co.uk/mills/tinytech.htm

And the prices are "doable"

(7) STEAM POWER PLANT 8 HP
Steam power plant consisting of (1) Single cylinder double acting steam engine 8 hp, cylinder diameter 4" x stroke 4", complete with reverse mechanism, hand lubricating pump for cylinder lubrication, drip lubricator for crosshead lubrication and 12" pulley (2) Water tube Yarrow type boiler suitable for biomass firing with 70 sq ft heating surface including economizer and superheater, test pressure 300 psi, working pressure 160 psi complete with water feed pump, water level gauge set, pressure gauge, safety valve, fire grates and 20ft chimney 1 set + interconnecting pipe lines, valves, pipe fittings etc 
COST US$ 4400/- with CD

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## buenijo

Anti Federalist, I've been corresponding with Mr. Desai by email for a few weeks now. I do like what he's doing in trying to get small scale steam back in use. Those prices really are low. In fact, they're so low that I can't help but to wonder why. I recently asked Mr. Desai if he can make available all of the components of the engine unassembled and unpainted, and without feed pump or Stephenson link. I haven't yet received a reply on this, but I only just asked. If you do make a purchase, then perhaps consider this option. I've got my eyes on their 2 hp engine. At that price I don't think I can resist, ;-).

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## Anti Federalist

> Anti Federalist, I've been corresponding with Mr. Desai by email for a few weeks now. I do like what he's doing in trying to get small scale steam back in use. Those prices really are low. In fact, they're so low that I can't help but to wonder why. I recently asked Mr. Desai if he can make available all of the components of the engine unassembled and unpainted, and without feed pump or Stephenson link. I haven't yet received a reply on this, but I only just asked. If you do make a purchase, then perhaps consider this option. I've got my eyes on their 2 hp engine. At that price I don't think I can resist, ;-).


Awesome, I'm curious to see how he will reply.

I thought the same thing myself, that the twin eccentrics and Stephenson reverse gear would not serve much use on a stationary engine, since it can assumed that the engine will only need to turn in one direction for an industrial/generator load.

I could keep the feed pump though, that looks neat, I'm guessing it's a three stage, high pressure pump from a pressure washer.

I don't know if I'm going to make the leap though, I can imagine shipping and customs costing more than the unit itself.

ETA - Did you see the complete genset plants for roughly $2000 more? Trouble is they are 220v 50 cycle units and I have no idea how tightly they are regulating cycles or what process they use.

To me, it's much more simple to use this as part of three pronged, battery/inverter system using solar/wind/steam to keep the battery bank charged.



That will charge at 24 volts, 125 amps, internally regulated, one wire installation, all day long for an initial cost of roughly $300.

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## buenijo

Anti Federalist, I'll update you on his response. 

I'm not sure about the feed pump that he uses, but it looks like a diaphram pump. Here is a much better prospect for a feed pump: http://www.mcmaster.com/#pressure-washing-pumps/=mcck06 (see standard Hypro pressure washer pump). These piston pumps are available at various suppliers. I am aware of it being used as a feed pump in several steam boat applications.

I totally agree about using the system for battery charging. Here is another prospect for the alternator: http://www.windynation.com/jzv/p/267...tor?p=YzE9MTI= There are several models available. Personally, I like these permanent magnet alternators. I think they can work very well with a system designed for battery charging at a constant output where the power is low. BTW, my idea for designing a steam system involves using a low power engine to drive a PMA at a constant output to charge a battery without any charge controller. I'm trying to shed the system of all components that are not absolutely necessary. I feel that taking care to monitor the battery voltage regularly and adjusting the output of the steam system accordingly will be sufficient. A simple diversion load controller could be used as well.

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## buenijo

Anti Federalist, I got a reply from Mr. Desai. He notes that assembling his engines and testing them is necessary to identify any errors in machine work, and that disassembling the engines after assembly and testing would raise labor costs. It seems to me that if he's concerned about machining errors, then one had best opt for the fully assembled and tested engine before taking delivery. But his statements (along with the observations of Mr. John Todd) should raise eyebrows about the quality control of his operation. I guess you get what you pay for! Personally, if I were to make a purchase, then I would get two or three of the 2 hp engines (just the engines) listed at $650 each. This would provide redundancy and extra parts... just in case. I would provide my own feed pump and alternator.

Also, I strongly advise against anyone purchasing a boiler from this source. Limited quality control from a boiler manufacturer is not a viable option. So, unfortunately, steam power is not an option unless one is willing to build and test their own boiler. Good news is that it should be possible to construct a fairly low cost biomass furnace and monotube steam generator. At least, I'm convinced based on my research that this is possible provided the steam generation rate is limited to that sufficient to power a steam engine at 1-2 hp.

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## buenijo

Web Site: www.uniflowpower.com

EXCERPT:

"Small scale, affordable, reliable and robust steam engine generators have the potential to free off-grid households and communities from the need to purchase diesel or petroleum based fuels to generate power. This is particularly the case where a 'hybrid' renewable energy system, incorporating solar panels, or small scale wind turbines and a battery bank are already in place. Every one of these 'hybrid' systems will also have a petrol or diesel generator integrated into the power supply to enable the battery bank to be conditioned and recharged. A Uniflow Generator could replace those fossil fuelled generators.

The Uniflow Generator can produce more than just electricity. This versatile energy production platform can also deliver hot water, rotary mechanical power, wet or dry steam, and distillation if required from renewable fuels.

Because there is no internal combustion, the S5000 is very quiet. In applications where it is being used to replace a diesel or petrol powered generator the low noise of the S5000 will be an enormous improvement in comfort and utility, allowing operation of the device indoors (with appropriate ventilation or external flues) and right beside other activity such as community or health centres, schools or workplaces, without the imposition that the roar of internal combustion generators can create. 

The patented boiler does not use an accumulator, steam chest or 'pressure' cylinder but rather is a 'flash' boiler. We call it a 'steam generator'. If the mechanical power of the engine is not needed, the small and highly efficient steam generator can be used directly to produce either wet or dry steam, and thus deliver sterilizing, distillation, process heat, hot water and space heating depending on how the steam/water circuit is configured.

The Uniflow Generator has the potential to deliver a system that could comfortably power and heat an average suburban home, providing hot water, electricity and space heating, all from pelletised wood fuels. This is referred to as CHP, or combined heat and power. 

Using high quality pelletised fuels a Uniflow CHP system should produce no visible smoke and be able to be largely automatically controlled like other modern home heating system. A program of work is also underway to develop a system that would run off natural gas for those applications where use of renewable solid fuels was not practical and where gas is available."

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## Anti Federalist

////

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## RabbitMan

Fascinating thread guys, I never knew Steam power was still around, and for that matter, that it was actually practical!

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## Anti Federalist

> Fascinating thread guys, I never knew Steam power was still around, and for that matter, that it was actually practical!


It *built* the world we know.

Check this out, a *brand new* (not restored or antique) 100 mph steam locomotive in the UK.

The _Tornado_

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## Acala

> Fascinating thread guys, I never knew Steam power was still around, and for that matter, that it was actually practical!


This is one of the reasons I don't buy the peak oil hysteria.  The industrial revolution was well under way before oil undercut (or killed with politics) all other energy sources.  In fact, nuclear energy is really just steam with a new heat source.

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## osan

> Fascinating thread guys, I never knew Steam power was still around, and for that matter, that it was actually practical!


Steam is alive and well.  What do you think drives the generators at coal/oil fired electrical plants?  Nukes?

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## osan

> This is one of the reasons I don't buy the peak oil hysteria.


In terms of energy source, I may agree.  In other terms I am not so sure.  If peak oil is a fact, then we can look forward to famine and disease.  Almost all our fertilizers and most pharmaceuticals come from petroleum. 

Also, a return to life without plastics will not be pleasant.

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## speciallyblend

> In terms of energy source, I may agree.  In other terms I am not so sure.  If peak oil is a fact, then we can look forward to famine and disease.  Almost all our fertilizers and most pharmaceuticals come from petroleum. 
> 
> Also, a return to life without plastics will not be pleasant.


Hemp for Victory Baby this is our answer bottom line!! a strong majority of products today would be made out of hemp, anything plastic based basically. This is why marijuana is illegal!!  we have to stop the 75 yrs of lies on marijuana and industrial hemp ,cannabis sativa !!!

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## Travlyr

Not to derail this thread... nonetheless... *Hemp for Victory!*

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## speciallyblend

> Not to derail this thread... nonetheless... *Hemp for Victory!*


yeah i love the idea of making a steam engine,just lack the $$$$$$$!! back on topic    of course you could burn your left over marijuana stalk and materials in your steam boiler

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## Acala

> In terms of energy source, I may agree.  In other terms I am not so sure.  If peak oil is a fact, then we can look forward to famine and disease.  Almost all our fertilizers and most pharmaceuticals come from petroleum. 
> 
> Also, a return to life without plastics will not be pleasant.


Chemical fertilizer is great for producing massive quantitites of unhealthy food in an unsustainable way.  Same for pesticides.  A transition to locally-grown, organic, open-pollinated crops will be good for us in the long run.  But the transition will not be without pain.

The majority of pharmaceuticals are useless or worse.  Most of those that are valuable can be derived from natural sources.

Are you really going to bemoan the loss of PLASTIC?  Wow.  I hate plastic.  There is very little made of plastic that cannot be made more durable, more beautiful, and less toxic from wood, glass, ceramic, or metal.     

But I guess I am a 1900 kind of guy.

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## Anti Federalist

///

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## osan

> Chemical fertilizer is great for producing massive quantitites of unhealthy food in an unsustainable way.  Same for pesticides.  A transition to locally-grown, organic, open-pollinated crops will be good for us in the long run.  But the transition will not be without pain.


Sort of beside the point, though.  We ARE using chemical fertilizers and are making very little effort not to.  Also, though the food may be shyte, it still keeps people fed.  If the food production drops by 60% suddenly, lots of people will go hungry and lots of those will starve, which in turn leads to unpleasantness like rioting and war.  We are in a corner.  How to extricate ourselves?  Some people get it - most do not.




> The majority of pharmaceuticals are useless or worse.  Most of those that are valuable can be derived from natural sources.


Do you have a source for this assertion?  Sulfa drugs come from oil and coal.  Many ABX do as well.  These are not useless.  Whence springeth Viagra, I cannot say.




> Are you really going to bemoan the loss of PLASTIC?


I am not bemoaning anything.  I am simply stating what will be.




> Wow.  I hate plastic.


Hate is a very strong word.  I certainly do not hate plastic.  Without them, much of what is good in our lives would be impossible.  Yeah, they have entries in the negative column as well.  Everything has a price.  Whether that price is fair... that is a matter of individual opinion.




> There is very little made of plastic that cannot be made more durable, more beautiful, and less toxic from wood, glass, ceramic, or metal.


This is actually very incorrect.  There are some applications for which plastics are the ONLY viable solution, but let us not even dwell on that.  



> But I guess I am a 1900 kind of guy.


If tomorrow you were forced, and I mean FORCED to live this Luddite vision, I predict that within a year, assuming you lived that long, you would sell your mother to a brothel in exchange for a return to the here and now.

Consider a simple padlock.  You need one.  You get in your car and go to the store and pay $5 and have your lock.  If you want a really good one, maybe you pay $45.  Now go back to the good old days.  You need a lock.  You get in your wagon, after you feed the horses, muck the stalls, harness them up, and then ride 3 hours to go the 15 miles into town where you find the local blacksmith who can make you the lock in about a week at a cost of about $700 (if you have never made a padlock - a good one - you do not know how much work it is.  Trust me, it is a lot.  In town there is horse $#@! everywhere.  It stinks to heaven.  We coudl go on, but perhaps the point is clear?

Many people hold a romantic view of the "good old days".  They were not that good in many, many respects.  In some others, they were better.  Everything has its costs.  This hopelessly naive opinion that so many hold of the virtues of a return to the 18th century bucolic life are perhaps born of contemporary stresses.  This is understandable, but falling for the phony baloney nonsense that, say, movies such as Avatar vomit forth in such fecund abundance is not wise.  People want what has never been and never can be.

My grandma lived the life to which you allude.  Her life was rock hard and I'd bet money I don't have that you would not want to live that way.  She knew how to raise it, kill it, cook it.  She still welcomed modern medicines and considered them great blessings because common diseases, those to which we no longer give the proper respect, used to kill people on a grand scale.  Children died at rates that would make many people today ill to think of it.  In so many ways the life you mention was hard and wretched and $#@! came out of nowhere and it did not matter whether you were dirt poor or choking on wealth - death came out of nowhere and took you suddenly.  If that is what you want, by all means get off at Willoughby.  There is much of this modern world that I find of questionable merit, but there is also a lot that I would not wish to do without if I had my druthers.

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## Anti Federalist

> If tomorrow you were forced, and I mean FORCED to live this Luddite vision, I predict that within a year, assuming you lived that long, you would sell your mother to a brothel in exchange for a return to the here and now.


Wow, how to approach this...

Listen, your points are valid and powerful, much about the "good old days" wasn't very good at all.

But I do question this technological terror we've created for ourselves. Consider your point about the advances in medicine that helped, in literally 100 years, slay that stalking specter of death you were alluding to, that people up to that point had to always be on the lookout for.

But in exchange is the knowledge that, in labs all around the world, there are "bugs" being worked on with the very latest in scientific and technical knowledge, that, if ever released, on purpose or "accidentally", would wipe **** sapiens sapiens from the face of the earth.

Or the advances in communication technology, it was only 100 years ago or so that spark gap Morse code transmitters were invented. Compare that to the wireless network all around us and the great leaps in prosperity that has brought.

While at the very same time, that same technology has now created a surveillance matrix that can, quite literally, cover the globe. It will only be a matter of 20 years or so, before there will be no corner of the planet outside the reach of global big brother and his systems of monitoring and control of every single human being on the face of the earth.

The simple joy of looking up at the night sky and gazing upon the heavens has been taken from me, since, while I am looking up, I know in my mind that there are innumerable tools of god knows what government agencies, always looking down at me.

Certainly, there are some people that have an unrealistic view of the "bucolic existence" that past generations may have had, certainly, for most people, then, as it is for most people on the planet now, life was "hard, brutish, nasty and short". The idyll that is in most people's mind comes from literature that was written by, or from the perspective of people, enjoying what the Romans used to call "otium": perfect leisure, provided for by servants, slaves, and huge amounts of liquid cash.

They could gaze out at cows in a serene field, they didn't have to get up at 0400 to milk them.

I've experienced the same thing, people gazing wistfully at scenes of fishermen like myself, mending nets on the dock, never considering how that net got torn up in the first place, during a storm in the middle of the night while hung up on rocks, destroying your gear and your catch in the bargain.

I'm well aware of the scars and damage done by "living close to the earth", I've been doing it all my life, and am paying the price in aches, pains and ailments now, in my later years.

But, all things carefully considered, while perhaps I would not want to take my chances in 1800, honestly, I think I could live quite comfortably in 1900.

I'll cheerfully accept the sobriquet of "Luddite" for that.

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## Anti Federalist

///

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## axiomata

Anti-

Sounds like you still would like to put some of the blame on the tools instead of the wielders of the tools.

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## Anti Federalist

> Anti-
> 
> Sounds like you still would like to put some of the blame on the tools instead of the wielders of the tools.


Guilty I suppose.

There are just some "tools" that I cannot fathom or justify, race specific, 100 percent mortality bioweapons for example or implanted RFID tracking chips.

There's very little or no "upside".

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## osan

> Wow, how to approach this...
> 
> Listen, your points are valid and powerful, much about the "good old days" wasn't very good at all.
> 
> But I do question this technological terror we've created for ourselves.


We do not disagree, but also recall my point that EVERYTHING has a cost.  There are no exceptions to this.  Ever.

That said, overall where would you rather be?  Here, now - or then?  I would refrain from answering quickly.  This is the sort of question that should take a good long time to sink in and the possible answers given careful consideration.

Go back 1000 years.  Flu, broken bones, minor puncture wounds... all could be fatal or brutally maiming events.  Consider human relationships: you are a smallish woman and the person bearing upon you is a large male brute.  The chances you will prevail are just this side of none.

Return to now: flu is still dangerous, but can most often be weathered - far more so than back in the day.  Broken bones suck, but typical breaks are mended with no lasting ill effects.  A little neosporin and a bandaid renders most small punctures readily healed.  A small frame .357 magnum pistol neutralizes the brute's great advantage in mass and strength, reducing the tete-a-tete to a contest of attitudes.

No doubt the prices we have paid have been high.  In some cases, too high I agree.  But what shall we do?  We are where we are and a return to earlier times is perhaps not an option for the world at large.  There are now WAY too many people to be able to return to the lifestyle of 1900, much less 1800 or earlier.  The only reason the world sustains this many human beings is our technology.  The food may not be as nutritious as it was, but we produce a hell of a lot more of it.  We could never produce such yields without modern methods.  That went on long enough, in conjunction with advances in medical practice, to allow the population to swell to what is now approaching 8 billion souls.  Cut off the mass agriculture and half the world would be dead within a year, guaranteed.  Organic means simply cannot provide the volumes required, and here I do not mean the organic in the usual commercial sense.




> Consider your point about the advances in medicine that helped, in literally 100 years, slay that stalking specter of death you were alluding to, that people up to that point had to always be on the lookout for.
> 
> But in exchange is the knowledge that, in labs all around the world, there are "bugs" being worked on with the very latest in scientific and technical knowledge, that, if ever released, on purpose or "accidentally", would wipe **** sapiens sapiens from the face of the earth.


This is not a problem of the technology, but of the human animal.  This is the product of several factors that, taken as a whole, can produce truly horrific results.

Or the advances in communication technology, it was only 100 years ago or so that spark gap Morse code transmitters were invented. Compare that to the wireless network all around us and the great leaps in prosperity that has brought.

While at the very same time, that same technology has now created a surveillance matrix that can, quite literally, cover the globe. It will only be a matter of 20 years or so, before there will be no corner of the planet outside the reach of global big brother and his systems of monitoring and control of every single human being on the face of the earth.

The simple joy of looking up at the night sky and gazing upon the heavens has been taken from me, since, while I am looking up, I know in my mind that there are innumerable tools of god knows what government agencies, always looking down at me.

Certainly, there are some people that have an unrealistic view of the "bucolic existence" that past generations may have had, certainly, for most people, then, as it is for most people on the planet now, life was "hard, brutish, nasty and short". The idyll that is in most people's mind comes from literature that was written by, or from the perspective of people, enjoying what the Romans used to call "otium": perfect leisure, provided for by servants, slaves, and huge amounts of liquid cash.




> They could gaze out at cows in a serene field, they didn't have to get up at 0400 to milk them.


You make my point in a backhanded way.   Generally, people desire what they do not have and do not understand.  I raise livestock and it is a $#@!ing pain in the ass.  I may even give it up, especially now that my wife will be undergoing chemotherapy and the changes this stands to bring to our lives.

People are well intentioned dumbasses.  They mean well, but have not the means of doing good.  This is largely because they think simplistic solutions for everyone are the answer.  One size does NOT fit all.  The sooner we come to grips with this, the sooner we can save ourselves a trip back in time to the days of the cave man.




> But, all things carefully considered, while perhaps I would not want to take my chances in 1800, honestly, I think I could live quite comfortably in 1900.
> 
> I'll cheerfully accept the sobriquet of "Luddite" for that.


1900?!!  I don't know how old you are, but I lived in NYC at the end of the industrial era.  It was FILTHY - hell, the Hudson is still murky, but in those days, entering that water could get you killed.  The stench in NJ along the Pulaski skyway was tremendous and the statistical distribution of cases of lung disease in such places was skewed significantly.  The Meadowlands has sixty thousand  tons of mercury dumped there - all from that era.  1900 was filth and pollution and death and disease running rampant.  Not only did you have the classical threats as listed above in part, you had the aggravating factors of horrific poisoning of the local environment.  you'd be better off in 1800 as the medical practice was about the same and the great $#@!ting on the environment had yet to begin.

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## Kelly.

does anyone know how much torque those tesla turbines are capable of?
it seems like a big stream tank (like in the first post/pic) and a few efficient tesla turbines, pair with alternators might be able to produce a good amount of power. 

i would also like to see a tesla turbine combined with a magnetic cog ( cog info here ) as this seems to reduce the losses with pulleys/gears.

i am/have been working on a mini newman motor as well as a way to capture the back EMF, but havent really messed with it in awhile...
great topic btw

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## buenijo

"_People are well intentioned dumbasses. They mean well, but have not the means of doing good. This is largely because they think simplistic solutions for everyone are the answer. One size does NOT fit all. The sooner we come to grips with this, the sooner we can save ourselves a trip back in time to the days of the cave man_." Osan


Exactly! ;-)

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## buenijo

Just sharing more thoughts on steam power. I emphasize (again) my opinion that a small steam system can work for powering a small off grid home, but only if certain conditions are met. These conditions include:
1. Fueled by a wide range of biomass with minimal processing requirements (i.e. stick wood, split wood, shredded pine needles, paper shred, lawn clippings, etc.)
2. Low and constant output for extended periods at low speed. Low speed reduces wear on engine. Constant low output simplifies #3.
3. Put the waste heat from the steam system to full use. Hot combustion gases from the furnace can dry fuel. Steam exhausted from engine can heat home, heat water, dry food, pasteurize (water, milk, beer, fruit preserves, etc.), dry clothes (hey, why not?), and provide air conditioning*. 
4. The system must be devised for extended and UNATTENDED operation. An old school system that requires one to baby sit the boiler is a nonstarter. The system is best served by a gasification furnace similar to those on wood gasification boiler systems that use seasoned fire wood as fuel.
5. Must use a compact monotube steam generator as opposed to a boiler.

One major benefit of this kind of system is often overlooked. A system that operates for extended periods at low power, and on demand like a small steam system, can allow a much smaller battery system to be used as compared to other off grid configurations. This can save literally thousands of dollars on the initial purchase of batteries, but a lot more money can be saved in the long run. This effect can be optimized by various means, but the general approach is to distribute loads around the operation of the steam system to minimize the discharging of the battery system. While the steam system is operating it could also be heating a store of water (a thermal mass) for heating applications. Also, with particularly low speeds and attention to rugged design, then a system might be operated literally most of the time. Such a system might show a particularly low power rating to further minimize the size of the system. Personally, I believe a system at only 1/2-1 hp is sufficient for most off grid residential scale applications.

*AIR CONDITIONING WITH HEAT: Using steam for heating applications is straightforward. Using steam to provide air conditioning can be done through various means, but not without some ingenuity. For those who may be interested in trying this, I recommend ammonia absorption. However, in most cases providing air conditioning in the off grid setting should best be done with photovoltaics used to power conventional vapor compression systems. The only setting where a small biomass fueled steam engine might make sense would be a cold climate with extended periods of low solar insolation and where wood is already used as a primary source of heat. Under these conditions a steam engine system could provide all the heat, but it could also provide a lot of electricity.

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## buenijo

Osan, I enjoy reading your thoughtful posts. This discussion has caused me to consider more thoroughly the impetus behind the increasing interest in going "off grid". It does appear to be a growing trend. I can't speak for others, but I am personally concerned about being dependent on a system that I see as unstable and corrupt. As individuals we are dependent on one another in this modern society. I welcome the kind of interdependence fostered under a free market system. However, most who frequent this forum understand that the U.S. is not a free market system. I see the U.S. economy and social structure as artificial in many respects. Its current structure did not develop in a sustainable manner. Therefore, maintaining the current structure requires a continuation of the interventions that shaped its development. Unfortunately, the kind of central control that characterizes these interventions have no hope at all in organizing the capital structure of our economy for increased productivity, nor is there any hope of their affecting our social institutions in a positive manner. We're approaching a terrible crash that can take many forms. So far I am not optimistic that there are a sufficient number of individuals in the U.S. who understand how far down the rabbit hole we are, nor how bad things can get. What concerns me most of all is how much increased interventions the citizens of the U.S. will tolerate from our government should conditions deteriorate further. For example, if the U.S. economy were to take a dramatic leg down in the coming years with continued high unemployment and escalating inflation, then I fear (and expect) the populace to demand ever more imaginative interventions from our government. For this reason I am convinced that any fundamental reform can take place only after the current system in place collapses. If this takes place, then which path will we take? Are there enough individuals in the U.S. who understand liberty well enough to recognize and support leaders who will protect it? There is reason to hope, but I still see too much nonsense to call myself an optimist on this matter. Thinking along these lines since 2005 has led me to my current lifestyle of simplicity and frugality. I have zero debts, I rent a small house, and I save real money. I suppose my interest in going "off grid" is the next step in this process. In summary, I simply abhor the idea of being dragged down this rabbit hole against my will. I cannot avoid being affected by the trends in place, but that doesn't mean I have to cooperate.

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## osan

> does anyone know how much torque those tesla turbines are capable of?


As much as any other turbine, minimally - once up to speed.  An impulse turbine is my idea of the way to bring the tesla elements up to operating velocity, at which point it is declutched from the operating gang.

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## Kelly.

> As much as any other turbine, minimally - once up to speed.  An impulse turbine is my idea of the way to bring the tesla elements up to operating velocity, at which point it is declutched from the operating gang.


i saw somewhere a guy was saying that if you can get the disc size and spacing correct, the tesla turbines can be 97% efficient  

i have see a bunch of pulse type motors, but i dont seem to recall any with high enough torque to spin a decent sized generator.

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## buenijo

YouTube video showing a simple biomass gasifier furnace. http://www.youtube.com/watch?v=otzTpr4C_m8 

Check out how he processes his wood fuel here (fascinating!): http://www.youtube.com/watch?v=SXJCS...el_video_title

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## buenijo

WEB SITE: http://solarfire.org/Solar-Fire-P32-Description

Excerpt from web site: "Testing is currently being done, but the expected performance is 15 kilowatts of steam energy in broad daylight. This steam energy can be used directly to purify large quantities of water, boil milk, produce edible oils, make charcoal for terra-pretta, bake bricks, make paper, recycle materials, and anything requiring heat.

The steam can also drive a steam engine to directly power a water pump, oil and grain mills, cotton spinning, juice presses, or any (stationary) application requiring mechanical power. With direct power (no electricity) such systems are easy for villagers to install and maintain.

Each concentrator is an autonomous source of energy (a sort of solar energy outlet) that can provide energy independence from fossil fuels and greatly reduce dependence on biomass.

Electricity? Solar Fire is not designed with electricity in mind but rather to replace fires of biomass and coal, specifically in developing countries. However, the energy can also be transformed into electricity by a steam engine and generator for lighting, recharging mobile phones, etc.

With the Solar Fire P-32, if the steam is converted to mechanical power and then electricity the result should be about 1.5 to 3 kw of electricity (testing will be performed shortly). So, only a small part of our steam energy can be converted to electricity (at the small scale). However, when used locally this “waste heat energy” from the steam engine can be easily used for boiling, drying fruit, heating spaces, pasteurizing, and so on. When we consider these secondary applications, the majority of the waste steam energy need not be wasted."

MY COMMENT: I love the simple design. In its current form it requires an operator to continually adjust the position. However, I can think of all sorts of fairly simple ways to automate it. The estimated electricity generation rate of "1.5 to 3 kw of electricity" from a steam engine powered by this system is overly optimistic. If the peak power is 15 kilowatts of steam production, then the piston engine that is shown in the video would produce electricity at a peak rate of about 700-800 watts. I think these folks meant to write "1.5 to 3 *kwh* of electricity". This would be a solid conservative estimate of output for a single day of operation from such a simple steam engine, particularly when considering less than peak output during most of the time. Of course, the inventors do emphasize that the primary intended applications for this system is not electricity production.

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## Kelly.

^^^^^
one of those + sterling engine + a generator = power?
im sure it would work, but i wonder if it would be more or less efficient then just charging batteries with a pv array.

edit: i realize these are designed for electrical power generation, but i think that should be the goal. even on a small scale decentralized power would be a huge step in the right direction.

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## buenijo

Hi Kelly. Sorry for the long post, but I have acquired a lot of knowledge on this topic, and developed strong opinions along the way. 

A stirling engine would certainly work, but not necessarily any better than a steam engine. In both cases (steam or stirling engine) it's difficult to build an engine that's cost effective, powerful, and highly efficient. If mechanical power is needed, and if the waste heat can be put to use in other processes, then a simple steam engine does makes a lot of sense in the applications suggested in the video (especially in the "third world"). 

Now, if electricity is the only desired product, and a cutting edge heat engine is not available, then I say PV is the way to go. A PV array of the same surface area would generate a lot more electricity than the simple steam engine used in the video. However, cutting edge heat engines can be a lot more efficient than PV in generating electricity. For example, SES built a solar powered stirling engine that can generate grid quality electricity at 30% net efficiency (under ideal conditions). Infinia developed their "Power Dish" that is capable of 24% peak efficiency (again, under ideal conditions). Even under typical conditions the efficiency of these cutting edge solar stirling engines should be about twice the efficiency of most PV systems. Unfortunately, these stirling systems are expensive, heavy, bulky, and technologically advanced (i.e. Infinia's Power Dish has a rated output of 3.2 KW at 1900 lbs, and costs $30,000)... but I do admit they are really cool. Check out the Power Dish here: http://www.infiniacorp.com/powerdish.html 

I believe that a modern steam engine offers some advantages in the solar application. One start up company Cyclone Power Technologies is developing a 5 hp solar steam engine. This engine weighs only 20 pounds. Its efficiency will be lower than the modern solar stirling engines, but it will be better than PV. More important, a steam engine will see a near constant efficiency during operation. So, the stirling engine will be more efficient than the steam engine... but not so much more efficient as "peak" efficiency numbers would suggest. Most important, the modern solar steam system will be A LOT less expensive and simpler. Consider that if the fuel is free (solar), then it's not efficiency that matters! In this case, efficiency is a four letter word: C O S T! 

In particular, it seems to me that a modern solar steam system would be best suited for decentralized power since it can be simpler and less costly than other solar options. Of course, the modern solar steam systems are not yet available... we're just gonna have to wait and see how it turns out.

ADDENDUM: See www.terrajoulecorp.com Their system is truly brilliant. It's gotten some decent press in the last few years, but I still think it's under appreciated. Their configuration makes possible 24/7 electricity generation with 100% solar (NO batteries - energy is stored with pressurized high temperature water in insulated steel propane tanks) at outputs higher than 100 KW electrical (and that's AC folks) with an overall efficiency of 17% (that is, 17% of the solar energy incident on the reflector array is converted to AC electricity). They are using a large slow moving piston steam engine design last manufactured in the 1940's. SEE POST #175 for more details.

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## buenijo

I just came across an exceptional web site on wood gasification. What I like about the site is how it's written. The author is a very good writer (especially considering that English is his second language), and he provides many personal accounts of his experiences in building and operating gasifiers. He also throws in a bit of his personal philosophy and politics, but this shouldn't be too distracting to those here as he seems to lean libertarian (this only makes sense... socialists don't build gasifiers, they petition the government to do it for them - and have you pay for it).

HOME PAGE: http://woodgas.nl/GB/index.html

MICRO GASIFIERS: http://woodgas.nl/microgasifiers/microgasifiers.html

The discussion on micro gasifiers is SPOT ON! Now, I admit that I have little practical experience with wood gasification. I've done nothing beyond building and operating a few small updraft units. However, the discussion here confirms all of my research on wood gasification. The bottom line is that designing, building, and operating a large wood gasifier is a lot easier than doing so for a small one. A small unit suitable for powering an internal combustion engine reliably over an extended period of time must be built to perfection, and the fuel must also be processed to perfection. Since my interest is combined heat and power for a small off grid home with emphasis on simplicity and reliability, I shifted my focus toward small scale steam power. A micro gasifier might be great for emergency power when nothing else is available, but I'm convinced that it's not practical for someone to go totally off grid. A large unit used to power multiple homes in a small community is a different story.

Also, here are two of some of the best resources on wood gasification available online!
Wood Gas as Engine Fuel: http://www.fao.org/docrep/t0512e/T0512e00.htm
Handbook of Biomass Downdraft Gasifier Engine Systems: http://www.tpub.com/content/altfuels01/0276/index.htm

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## Danke

http://d.yimg.com/kq/groups/7769081/...e/Tornado1.wmv

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## buenijo

Description of a solar powered ammonia absorption ice maker: http://www.free-energy-devices.com/P13.pdf 

The most complicated part of this system appears to be the solar concentrator. Using the heat from a small biomass furnace directly could be a lot simpler (something akin to the "wood gas camp stove" could be ideal: http://www.youtube.com/watch?v=Z6evSvYH_RA). A freezer powered by a small batch loaded updraft biomass gasifier sounds very appealing! I believe that a small chest freezer that would normally consume 1 kwh of electricity each day could be powered by such a system with about 3 pounds of wood fuel each day.

Other links: http://www.energy-concepts.com/isaac
http://www.savethefood.org/

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## Kelly.

pretty cool, please keep posting stuff here

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## buenijo

FEMA Document: "Construction of a Simplified Wood Gas Generator for Fueling Internal Combustion Engines in a Petroleum Emergency".

http://www.gengas.nu/byggbes/index.shtml

This document describes a very simple wood gasifier design. Unfortunately, this design is well known among gasifier enthusiasts to produce a dirty gas high in tar. It is not considered suitable for powering an engine reliably for an extended period of time. However, I consider this document a good introduction to wood gasification. The following excerpt is a good description of the process:

"1.2 PRINCIPLES OF SOLID FUEL GASIFICATION 

All internal combustion engines actually run on vapor, not liquid. The liquid fuels used in gasoline engines are vaporized before they enter the combustion chamber above the pistons. In diesel engines, the fuel is sprayed into the combustion chamber as fine droplets which burn as they vaporize. The purpose of a gasifier, then, is to transform solid fuels into gaseous ones and to keep the gas free of harmful constituents. A gas generator unit is, simultaneously, an energy converter and a filter. In these twin tasks lie its advantages and its difficulties.

The first question many people ask about gasifiers is, 'Where does the combustible gas come from?' Light a wooden match; hold it in a horisontal position; and notice that while the wood becomes charcoal, it is not actually burning but is releasing a gas that begins to burn brightly a short distance away from the matchstick. Notice the gap between the matchstick and the luminous flame; this gap contains the wood gas which starts burning only when properly mixed with air (which contains oxygen). By weight, this gas (wood gas) from the charring wood contains approximately 20% hydrogen (H2), 20% carbon monoxide (CO), and small amounts of methane, all of which are combustible, plus 50 to 60% nitrogen (N2). The nitrogen is not combustible; however, it does occupy volume and dilutes the wood gas as it enters and burns in an engine. As the wood gas burns, the products of combustion are carbon dioxide (CO2) and water vapor (H2O). 

The same chemical laws which govern combustion processes also apply to gasification. The solid, biomass fuels suitable for gasification cover a wide range, from wood and paper to peat, lignite, and coal, including coke derived from coal. All of these solid fuels are composed primarily of carbon with varying amounts of hydrogen, oxygen, and impurities, such as sulphur, ash, and moisture. Thus, the aim of gasification is the almost complete transformation of these constituents into gaseous form so that only the ashes and inert materials remain. 

In a sense, gasification is a form of incomplete combustion; heat from the burning solid fuel creates gases which are unable to burn completely, due to insufficient amounts of oxygen from the available supply of air. In the matchstick example above, as the wood was burned and pyrolyzed into charcoal, wood gas was created, but the gas was also consumed by combustion (since there was an enormous supply of air in the room). In creating wood gas for fueling internal combustion engines, it is important that the gas not only be properly produced, but also preserved and not consumed until it is introduced into the engine where it may be appropriately burned." 

MY COMMENT: With the match example in mind the operation of a simple updraft biomass gasifier furnace like the wood gas camp stove makes perfect sense. (See wood gas camp stove here: http://www.youtube.com/watch?v=pyofh...el_video_title). Combustion is started at the top of the fuel pile. Air is then admitted into the base of the fuel pile to support continued combustion. The heat generated by this combustion gasifies (pyrolyses) the surrounding fuel. There is not enough air admitted into the base of the fuel pile to combust all of the gases generated. Therefore, additional air is admitted through the upper air ports. This achieves "secondary combustion" of the wood gas. This is just like a match. The phosphorus on the match tip starts the process. The heat generated by the phosphorus pyrolyses the nearby wood of the match to release a gas. This hot gas mixes with air to burn. The heat from the combustion of this gas keeps the process going until all the wood in the match is pyrolysed to char. A gasifier attempts to control this process to generate a combustible gas that can be burned separate from the fuel source. That is, it allows a small portion of the gas generated in the gasifier to burn, and this heats the fuel causing it to release more gas to be piped away for remote combustion. Once this is understood all kinds of configurations can be imagined. However, note that a gasifier used to generate an engine grade gas uses a somewhat more complicated process. See post #127 in the following thread: http://www.ronpaulforums.com/showthr...-Engines/page5 for a more detailed description of the process.

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## AFPVet

The interesting thing is that even modern power plants still use steam to produce poweralbeit, different sources of fuel are used.

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## buenijo

Short articles on the use of electricity by the Amish. 

http://amishamerica.com/do-amish-use-electricity/
http://amishamerica.com/do-amish-use-batteries/

I was surprised to learn that many Amish often make use of electricity and Diesel engines. However, all references that I have seen show that all Amish are "off grid". Anyway, I thought it was interesting.

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## Anti Federalist

Lister diesel generator, new, 3000 watt, burns .3 GPH at full load.

http://www.generatorsales.com/order/...sp?page=L09912

Almost as good as steam, and with no computers or direct electronic injection, it should run just fine on vegetable oils.

In fact, the site offers a vegetable oil conversion, for an added cost.

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## buenijo

Anti Federalist, you might like this: http://www.powercubes.com/listers.html

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## buenijo

I've been looking into a continous ammonia absorption cycle as heat-powered chilled water system for air conditioning.  The description and diagram provided at this link http://vintageservelrefrigerators.8k...owItWorks.html is the best I've seen for explaining how a continuous ammonia absorption system works. I believe that this approach has potential for providing air conditioning in an off grid setting. It's already being used to provide refrigeration for food, but I know of very few examples where it is used to cool a home. I believe the reason that we don't see it is primarily due to the widespread availability of cheap electricity. A commercial system suitable for cooling a home would be prohibitively expensive for most people. Therefore, most off gridders either live where the heat is not oppressive, they tough it out, or they use generators to power vapor compression systems (like window units). Right now I think it's practical to power a/c units with photovoltaics where the units are operated primarily as opportunity loads (i.e. while the PV array is producing) as this will prevent or lessen battery discharge. However, the prospect of an efficient chiller powered by a wood furnace is intriguing.

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## Kelly.

> Lister diesel generator, new, 3000 watt, burns .3 GPH at full load.
> 
> http://www.generatorsales.com/order/...sp?page=L09912
> 
> Almost as good as steam, and with no computers or direct electronic injection, it should run just fine on vegetable oils.
> 
> In fact, the site offers a vegetable oil conversion, for an added cost.


i believe this is a lister knock off from india, not a genuine lister.
i know a family in my area that bought 2 of these listeroids as back up generators for their off grid home (homebrew wind and solar are primary) 

i havent been up there to check it out, but the price from the site you listed is pretty close to what they paid through a guy in kansas city.
im thinking i would like to get one of these as a backup generator, or as an attempt to kick start my "off grid in the city" plan...

cool to see it can be run off of other gases, but i dont think i would go through the trouble of converting it.

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## acptulsa

> I was surprised to learn that many Amish often make use of electricity and Diesel engines. However, all references that I have seen show that all Amish are "off grid". Anyway, I thought it was interesting.


Using a generator doesn't really make you 'on the grid'.  And around here, at least, the only Amish who use them are the ones that run restaurants, or have other legitimate need for refrigeration.

They tend to have cars, too.  Generally one optionless minivan per community.

Once upon a time, the railroads used steam powered air conditioners on passenger cars.  The compressor was simply turned by a steam-fed piston.  Hate to think how hard it would be to find one, but it really wouldn't be that hard to run a belt to a compressor...

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## Luciconsort

all this stuff is friggin awesome.... i used to think about all this stuff when i was a kid. years of slavery squashed those ideas... i'm starting to remember and i am VERY excited!

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## buenijo

acptulsa,

My comment should be read: Amish use electricity... however, they're still off grid. In other words, I agree with you. However, I now find myself having to qualify my position.

In my opinion, a system should not be considered as "off grid" if the only cost-effective and/or viable fuel available is provided through a highly capital intensive infrastructure (particularly one under central control, highly subsidized, and using unsustainable techniques). This should include not merely Diesel fuel, but low cost vegetable oils produced using modern farming techniques. Under these criteria, the only truly "off grid" systems that I can think of off hand include those fueled by biomass, direct solar energy, water, geothermal, wind, and biofuels produced under certain conditions.  

BTW, I'm not aware of steam powered vapor compression systems being used on railroad passenger cars. However, some used steam directly from the boiler to power a steam jet pump system using water as the refrigerant. See description here: http://research.atsfry.com/Passenger/pass_ac.htm. I discussed this system in another post in this thread. I think this system is viable for providing air conditioning in an off grid setting, but it's difficult to get high efficiency. Absorption/adsorption systems are also possible candidates. NOTE: Powering a mechanical compressor directly with a steam engine would avoid a lot of energy conversion losses in the alternator and compressor motor, and can be practical if the steam engine has good efficiency.

NOTE: The link above seems to be dead. Here is a lecture on lithium bromide absorption and steam jet cooling. Both use water as the refrigerant. http://www.youtube.com/watch?v=MKdpDLy7CLg

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## buenijo

Hi Kelly. Yes, I think it's a "Listeroid" too. Listers are no longer manufactured. By all accounts the quality of the Listeroids is dubious. BTW, I wouldn't convert it either. However, consider this: http://www.arrowengine.com/products/...r/K_Series.php. These are designed to be fueled "on a variety of low BTU gases; natural gas, methane, butane or propane." I see no reason why a good wood gasifier cannot be used to fuel these engines without modification. A better choice is probably a Honda engine as they are readily available and very reliable.

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## newyearsrevolution08

this is the sort of stuff that keeps me up at night LOL

I want a self sufficient medical marijuana grow under my belt before I die.

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## buenijo

Crosley Icey Ball http://crosleyautoclub.com/IcyBall/crosley_icyball.html A portable intermittent ammonia absorption system that was actually marketed and sold to provide refrigeration for food in American homes.

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## Anti Federalist

From the above ^^^ (great post BTW) plans to build a home made IcyBall

http://crosleyautoclub.com/IcyBall/H...irections.html

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## buenijo

Here's another good site that I just stumbled on: http://digital.lib.lehigh.edu/eb/supp/3646/index.pdf. This table lists the saturation conditions for aqua ammonia solutions from 0% to 100% ammonia. 

ADDENDUM: An ammonia absorption unit can use a fairly low temperature heat source under some conditions. First, it should be an air conditioning application with a fairly high evaporator temperature on the order of 40-45F. Next, the absorber and condenser temperatures must be driven down as low as possible. This could be done in most settings by using water cooling combined with a low cooling rate. This is also good for optimal dehumidification (that is, operating a unit for long periods at low cooling but with a sufficiently low temperature evaporator). Under these conditions  steam at atmospheric pressure can work well as a heat source - so the exhaust from a steam engine could be used without resorting to high engine back pressure to take the steam temperature up.

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## buenijo

===========

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## Anti Federalist

///

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## buenijo

I was checking out that "Icy Ball" again. What a simple design it is. AntiFederalist pointed out the home made version here: http://crosleyautoclub.com/IcyBall/H...irections.html. See diagram here:



The liquid check valve seems to be the heart of the system, and it appears to be very simple. I did a quick check for propane tanks that might serve this purpose and came across this: http://www.campingworld.com/shopping...b-1-gal-/56052. This appears to be a standard model. What I like about it is the fairly large threaded port right in the center of the top of the tank. A section of steel pipe could be threaded to fit and sealed with teflon tape. The internals of the liquid check valve could be designed to be integral with this pipe section with the entire unit just threaded right in. The rest of the system is straightforward. 

Here is a source for 29% ammonium hydroxide: http://www.chemical-supermarket.com/...lon--p670.html

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## buenijo

Hello all. I found a great well pump: http://www.simplepump.com/

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## buenijo

Good article on off grid living: http://production-images.webapeel.co...mp.Article.pdf. This describes a fairly versatile system with wind turbine, solar array, back up generator, wood furnace, propane appliances, and a large battery bank. I think the article provides a good discussion of the basics. This is an impressive system. Although, there are a few aspects that I find less than optimal. First, by my standards they should not be considered as totally "off grid" if they're using propane and a conventional back up generator. Second, that battery bank is rather large.

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## anaconda

I am very envious.

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## TruckinMike

> Just sharing my thoughts. I'm convinced that a small scale steam system powered by biomass is ideal for providing basic electricity, water distillation, and heat in an off grid setting. However, air conditioning remains a problem. So, I sat down to think a little more seriously about the viability of off grid air conditioning. My knowledge is limited, but I think I have enough understanding to make a case for the following:
> 1. The continuous ammonia absorption system is the best candidate
> 2. A pump is required to achieve high performance (*)
> 3. The system must see relatively high temperatures and pressures for high performance... *so, it should be fired by a furnace directly* ...


Instead of direct fire furnace how about building a heat exchanger*  with hot oil to heat the Ammonia solution. This way fine control is possible. Heating transformer oil to around 500 - 600 degrees can be easily done with a solar trough.  ( and at atmospheric pressure = safe)

* I read the previous post on heat exchanger materials. Solution - build a high surface area heat exchanger. -- 

Note: Heating oil instead of water gives you much greater flexibility in  your off-grid energy design. All you need is a multi-thousand gallon insulated tank to store your superheated oil. -- ready at a moments notice for home heating, water heating, steam conversion for steam electrical generator, ....And yes, for heating your ammonia absorption system as well.

Just a thought.

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## buenijo

> Instead of direct fire furnace how about building a heat exchanger*  with hot oil to heat the Ammonia solution. This way fine control is possible. Heating transformer oil to around 500 - 600 degrees can be easily done with a solar trough.  ( and at atmospheric pressure = safe)
> 
> * I read the previous post on heat exchanger materials. Solution - build a high surface area heat exchanger. -- 
> 
> Note: Heating oil instead of water gives you much greater flexibility in  your off-grid energy design. All you need is a multi-thousand gallon insulated tank to store your superheated oil. -- ready at a moments notice for home heating, water heating, steam conversion for steam electrical generator, ....And yes, for heating your ammonia absorption system as well.
> 
> Just a thought.


Thanks for the input. I have considered thermal oil. In fact, solar heated thermal oil was the first energy source I considered to power a small scale steam system. There are advantages, but the details required of such a system have led me to avoid it.

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## Anti Federalist

///

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## eduardo89

I was just watching a British tv series called Grand Designs where a couple restores a ruined mine engine house in Cornwall.



The amazing thing is it still has an intact smokestack which got me thinking that a steam engine for power and heat would be amazing in that building, especially given the building's history.

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## Anti Federalist

///

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## Kelly.

dear buenijo,
please come back, many are interested in what you may be doing

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## speciallyblend

http://www.hojomotor.com/?hop=29volt  can anyone tell me anything about this??? hojomotor?? waste of time??

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## eduardo89

> http://www.hojomotor.com/?hop=29volt  can anyone tell me anything about this??? hojomotor?? waste of time??


Probably. Anything that says it produces "free, clean, safe and unlimited electricity" so easy to build and with parts you can cheaply buy at the local hardware store is probably a scam.

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## pcosmar

> http://www.hojomotor.com/?hop=29volt  can anyone tell me anything about this??? hojomotor?? waste of time??


Waste of time.
Perpetual motion does not work due to the current Laws of Physics. (entropy)
You do not and never will get something for nothing.

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## amy31416

> Waste of time.
> Perpetual motion does not work due to the current Laws of Physics. (entropy)
> You do not and never will get something for nothing.


Heh. I remember when we used to get people posting that scammy crap on the forums all the time. Some people believed it too...I think my comment on it was something along the lines of: Congratulations. You've managed to not only produce energy, but solved the most confounding metaphysical question of how the universe came into existence--all for $79.95!

I think I went into a bit more detail about energy and matter, but you get the idea.

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## speciallyblend

> Heh. I remember when we used to get people posting that scammy crap on the forums all the time. Some people believed it too...I think my comment on it was something along the lines of: Congratulations. You've managed to not only produce energy, but solved the most confounding metaphysical question of how the universe came into existence--all for $79.95!
> 
> I think I went into a bit more detail about energy and matter, but you get the idea.


i figured it was a scam. I just thought i would see what rpf had to say about it thanks now back to steam!!

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## amy31416

> i figured it was a scam. I just thought i would see what rpf had to say about it thanks now back to steam!!


It really is an intriguing possibility. After we move and have the land, wood, equipment and privacy to do all this, we'll probably be experimenting with it ourselves.

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## klamath

Interesting discussion I didn't open it because I though it was all about steam but I see there are some pretty interesting side discusions. I spent my time working on _stream_ engines. I could really appreciate Osan posts as I have grown up and lived a lifestyle that started close to 19 century technology and evolved to satelite broad band internet.
I know too intimately what a Misery Whip is!

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## buenijo

> dear buenijo,
> please come back, many are interested in what you may be doing


Sorry to disappoint, but I'm in school these days. I won't be able to start any worthwhile AE projects for a long while. Although, I will eventually get my steam engine design working just to prove to myself (and others) that it will work well. Even a "simple" system like mine is going to be extremely difficult to build properly. I expect several years of trials and errors to be minimal. Most steam engine projects that you find on the web produce no usable power and the efficiency is absurdly low. I'm looking for something genuinely useful, and that's gonna be tough to produce. Even so, a biomass-fueled steam engine is not practical for powering a modern home, so it would interest only a select few who desire genuine self-reliance.

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## The Beastly One

> Is anyone selling small (5-20 hp) steam engines/boilers?  There are some enormous advantages to using steam to generate electricity - availability of fuel being among them.


Check out wood gasifier systems as well for fuel availability/concervancy issues. The advantage there is that nothing need be modified or added to existing engines to run them on wood gas.

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## buenijo

> Check out wood gasifier systems as well for fuel availability/concervancy issues. The advantage there is that nothing need be modified or added to existing engines to run them on wood gas.


Hey, check out the thread on gasification here: http://www.ronpaulforums.com/showthr...ustion-Engines. Please make some contributions to the discussion there if you like... maybe we can get that thread going again.

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## Simple

The sterling engine on a parabolic dish is a pretty good idea. I've looked into them but I haven't found any produced for home owners.There are a few companies working on them, I'm linking to Sunpower below. I have also seen the stirling's cool side water cooled for increased efficiency. 



http://www.sunpower.com/services/applications/solar.php

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## Kelly.

http://www.sunvention.com/

they have a large version of a stirling motor....

i would like more info on it if anyone can find it (ive seen the videos online, im looking for the big stirling info)

having a locally built stirling that can run 1500 watts during the daylight would be an awesome addition to any self reliant energy setup.

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## Simple

For any heat engine the best it can do is an efficiency of 1-(Temperature of the cold side/Temperature of the hot side)




> The SunPulse Electric is the core element of a decentralized autonomous energy system. It is an innovative low-temperature Stirling engine, which transforms heat energy to mechanical and electrical energy. In conjunction with a solar-heated hot oil system (see EPG) or pressurized hot water storage system it can provide energy day and night. Energy storage is thereby solved in a fundamentally different way than in established solar technologies, which often work with environmentally problematic storage materials.


So the bad part is since it is a low temperature system it will have low efficiency. The good part is using the oil or water to store heat energy allows for it to turn day and night. Sounds promising.

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## Kelly.

yeah, their system is pretty involved. they have a greenhouse and a hot oil storage tank, etc etc.

im more interested in even a version that would only run during the day via a solar concentrator or something similar. 
i like it because it is more versatile then the standard pv or wind setup. the stirling can provide mechanical power as well. 

i wonder if a stirling motor or a newman motor is cheaper to build?

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## buenijo

(deleted for its redundancy)

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## Liberty4life

> I will immediately call the authorities on this. How dare she produce electricity without the blessing of her governments! 
> 
> But yes, neat. I want to make a Sterling Engine, mounted to a heliostat, which I haven't been able to figure out how to build yet, with a parabolic mirror or frenel lens mounted to it and have a generator attached to it. Mount that whole deal to your roof.


OOO you stole my idea!!  j/k neat idea huh.  Tie that with an aquaponics system, a vermi(worm := heat/compost) composter, methane(natural) and hydrogen gas(by electrolysis) and you could create a powerhouse.

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## buenijo

FUEL ETHANOL PRODUCTION AT HOME (*)

It's actually fairly easy to build a reflux still to make 180+ proof ethanol in a single pass, and that's what I recommend for anyone who is dead set on doing this. Sure, a cheap pot still is great to get your feet wet, but anyone serious about producing their own ethanol fuel has to use a reflux still. The process is very simple, and I can explain it here. Note that while I have made my own wine for many years, I have never distilled it. However, I've done research on the process and I have an engineering background. Basically, you mix your sugar source in the proper concentration with water, then pasteurize it to kill bacteria and undesirable yeasts. Add your yeast and let it ferment to completion (usually a week or so). Now you're ready to use the still. The still is a pot with a reflux column. This column is simply a tall vertical pipe loaded with small rocks or marbles. The pot is insulated against heat loss. The column is not normally insulated, or it is weakly insulated. Now, a mixture of alcohol and water boils below 212F. As the vapors rise through the packing (i.e. the rocks) they continually condense and re-vaporize on the surface of the rocks (note that the heat lost from the column allows this, and the heat loss rate is important here - the best way to determine the proper rate is through experimentation). In effect, the column provides multiple distillations without using any extra energy or time inputs on your part. The most important element in the process is to keep the temperature at the top of the column within a very narrow range. The temperature you want is just above the boiling point for ethanol which is about 173F. The vapors enter the condenser immediately after they leave the top of the column, then you just collect the liquid ethanol. 

Yes, it's that easy.

* This discussion is relevant to this thread because saturated steam at or near atmospheric pressure (such as the steam exhausted from a steam engine) is an excellent source of heat for a fuel ethanol still. The steam can be passed through a copper heat exchanger placed in the pot of the still. A bit of tweaking would find the ideal parameters to allow for fully automated operation (without fancy schmancy electronic equipment because the temperature of the heat exchanger is set at a constant 212F). The boiling point of an aqueous ethanol solution is less than 212F, but the boiling point of the solution will rise and approach 212F as ethanol is removed. This will lower the temperature difference between the heat exchanger and the solution. So, the evaporation rate of the solution will also fall. However, the heat loss rate from the column will not fall. What will happen is as follows: some ethanol will condense before it reaches the top of the column as latent heat is lost from the alcohol vapors. While this will lower the overall efficiency of the system somewhat, it doesn't matter because you're using essentially free heat from the steam engine exhaust (besides, you still get most of the heat from the steam exiting the heat exchanger in the pot since most of it is not condensing there, and you can still harvest the heat from the column and ethanol condenser if you want to). The ethanol production rate falls as the distillation progresses, but the proof of the ethanol if anything will go up under these conditions. Now, once the vast majority of the ethanol has been removed from the solution, you will get virtually no evaporation (since the boiling point of the solution is now near 212F => no temperature difference => no heat transfer). So, in principle, it's possible for such a system to operate unattended, yield high proof ethanol, and with no dedicated control system... and purely mechanical. NOTE: The exhaust from a small steam system can be easily maintained at a temperature higher than 212F through various means, and keeping the temperature higher than 212F can ensure all ethanol is harvested from the solution. As long as a small steam system is operated at a constant output, then the still can be configured for this output to allow for a fully automated operation by sizing the column properly to allow for a sufficient heat loss rate to minimize carryover of water.

In general, this is economically viable only if you have a source of inexpensive fermentable sugars, and if you use a cheap source of heat for the distillation. For example, using electricity to power the still is not economical unless you put to use the heat thrown off the still (do the math, you'll see). On that note, anyone who wanted to the do this optimally should collect the heat from the ethanol condenser for heating applications (say, water heating). Hell, you could even put the still in a corner of a room when electric heat is used and use a fan to blow the heat around the room - this way you would catch ALL the heat. So, in principle, if someone uses electricity for heating, then using electricity to power a still could be done with all of the heat thrown off the still harvested for heating applications. Essentially, this would be like powering the still for free.

A good video: http://www.youtube.com/watch?v=DR7qIMMxH6Q

ADDENDUM: Adding zeolite to the aqueous ethanol solution that leaves the still can remove most of the water to achieve a 97-99% ethanol solution. This can then be blended with gasoline up to 50% and used to fuel modern automobiles directly. See Steven Harris as www.imakemygas.com. NOTE: It may be that silica gel (crystal cat litter) will work in lieu of zeolite.

ADDENDUM: Warning Not to Use E15 In Modern Cars (NOTE: It's hard to know what the truth is here since there are so many conflicting positions from "experts", but people should know both sides of the issue).

http://www.youtube.com/watch?v=ceW9Nc1hVHU

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## Anti Federalist

Bump

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## buenijo

I'm toying with an idea that I'll share on this thread since it involves steam. I remain convinced that a modernized piston steam engine with good thermal efficiency and fueled by biomass would be an ideal off grid power plant. However, until these become available I will consider other options. 

One of the main benefits of a piston steam engine is the ability to operate at very low power for extended periods while providing heat in a convenient package. Steam is an excellent heat transfer medium. So, I considered, why not devise a simple biomass fueled steam generator for heating applications? Furthermore, since my recent research shows that charcoal gasifiers can power very small engines cleanly and with impressive energy density, then how about a system that chars wood chips at a controlled rate and combusts the pyrolysis gases to generate steam on demand? The charcoal produced from the system can then be stored for use as required in fueling small engines.

I'm not suggesting how to devise such a system... just noting that it might be done.

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## buenijo

deleted

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## buenijo

See this study on steam jet cooling: http://www.crses.sun.ac.za/files/res...r/aj_meyer.pdf .

Interesting, but not likely competitive with alternatives..

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## buenijo

I've come across some studies on desiccant evaporative cooling recently. The skinny on those is that certain desiccants like some grades of silica gel have been shown to be regenerated (i.e. dried) using heated air with surprisingly low temperatures. I've seen good results from 130-170F. The lower the temperature the higher is the required air flow rate which should be expected. The exhaust from a small steam engine can easily provide these temperatures, and the air flow rate required would not be high. It's also possible to use solar heated air, or the exhaust from a wood gas engine system (and blower fan used to cool cylinder) could be used. NOTE: The idea here is that a desiccant can dry the air in a home, then the dry air can be used to support evaporative cooling.

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## buenijo

deleted

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## buenijo

Sanden is manufacturing scroll automotive compressors with belt drive. I believe these might make good expanders for use in organic rankine cycle engines. Unfortunately, the temperature of the waste heat from this kind of system is too low for use in many applications. Anyway, I think this is something worth trying. Please note it's necessary to remove the reed valve at the compressor discharge, and that the hot pressurized refrigerant vapor is then applied to the compressor discharge to operate the scroll in the direction opposite that it moves when used as a compressor (well, in theory anyway).

NOTE: Here is one small company working to develop this idea: http://www.eneftech.com/en/technology.php#turbine .

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## buenijo

http://tinytechindia.com/Template/in...TEAM%20ENGINES

Looks like Mr. Desai is now making steam engines by modifying AIR-COOLED DIESEL ENGINES. Based on the photos, it looks like he is mounting double-acting steam cylinders and valve assemblies to existing Diesel engines using the stock engine piston/cylinder as a crosshead. Looks like the quality of his steam engines just went up.

ADDENDUM: Price for a 2.5 HP engine including shipping costs is $1500. It seems to be a very robust design. It weighs 200 lbs, is about 30" tall, and the base is roughly 18" x 18". The bore is 2.48", and the stroke is 3.15". Based on these dimensions, the engine should put out more than 3 HP at 150 psi steam and 500 rpm. It's got a very long cutoff which is not good for efficiency, but it will provide a lot of power at low pressures and speeds. Best case for net efficiency here is about 4%. The best this engine could do under optimal conditions with a shortened cutoff is probably 6% net efficiency, and at that point it might be worth it... 4% is just too damn low. To reach the higher efficiency a smaller eccentric would have to be fabricated and the position of the eccentric on the shaft would have to be altered to get a steam cutoff of 25-33% of stroke. The steam quality would have to be high, and thermal losses from the boiler and all other places would have to be minimized with good insulation and other means. Getting 8% net efficiency is possible by using two engines in a compound configuration and bumping up the pressure to about 200 psig. Unfortunately, small scale steam power really needs serious upgrading before it can be practical. Without it, I must advise against it. Use a wood gasifier if power from biomass is desired. However, if you really can put the heat from a steam engine to use, then it can be a practical option.

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## Dr.3D

> http://tinytechindia.com/Template/in...TEAM%20ENGINES
> 
> Looks like Mr. Desai is now making steam engines by modifying industrial air compressors. Based on the photos, it looks like he is mounting double-acting steam cylinders and valve assemblies to existing air compressor systems using the stock air compressor piston as a crosshead. Looks like the quality of his steam engines just went up.


I see on this page... http://tinytechindia.com/Template/in...POWER%20PLANTS
(9) STEAM POWER PLANT 10 KVA (FOR ELECTRIFICATION) COST US$ 9000/- with CD
Not a bad price for so much.

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## Anti Federalist

> http://tinytechindia.com/Template/in...TEAM%20ENGINES
> 
> Looks like Mr. Desai is now making steam engines by modifying industrial air compressors. Based on the photos, it looks like he is mounting double-acting steam cylinders and valve assemblies to existing air compressor systems using the stock air compressor piston as a crosshead. Looks like the quality of his steam engines just went up.


Any videos of the new units in action?

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## buenijo

Recent Cyclone Power powerpoint presentation (part of presentation given at National Defense Industry Association).

http://cyclonepower.com/2013/Cyclone...4-23-13_v8.pdf

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## buenijo

> Any videos of the new units in action?


I haven't seen any videos of the new units. I see no reason why the new units should not be superior to the old units. Funny, but I think I may have first suggested this modification to Mr. Desai after he informed me that the city in which he lives is known for the manufacture of Diesel engines, but I can't be certain as that was more than a year ago. You see, modifying engines in this manner is not new. Either way, it seems a good decision to have done this. Now, if he would only concentrate on increasing the efficiency of the unit, then he might end up with a good product. 

BTW, at first I mistakenly believed Mr. Desai used an air compressor for the mod, but he is in fact using a two stroke Diesel engine.

NOTE: I believe it's worthwhile for someone with the inclination to acquire a small unit with the goal of modifying it for better performance, especially higher efficiency.

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## pathtofreedom

Internal Combustion engines are blasphemy

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## buenijo

I've made various speculations on providing air conditioning for a modest off grid home. I now take the position that a modest off grid home is best cooled by first minimizing heat gain through passive means. Air conditioning can then be had by powering small vapor compression a/c units as opportunity loads using photovoltaics. The cost of PV technology including the panels and the associated electronics have decreased so much, and their quality and performance has concurrently increased, that this is the most practical alternative in most cases.

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## Anti Federalist

////

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## Pericles

This thread should be stickied - just sayin'

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## Henry Rogue

My Father had an Advance Rumely willed to him by my Grandfather. My Grandfather also had a Nichols and Shepard, a Buffalo Pitts and a Case. They used them for farming early on, threshing and so on. In later years they used them for running the silo blower, steaming tobacco beds, running them in parades and steaming sweet corn at local town festivals. Here is a video of one similar to my Father's steam engine tractor, except his had brass bands wrapped around the boiler. The reserve water tank was also mounted in the back along with the coal box.


I helped load it on a flatbed a couple of times for parades. I steered and my Father operated the engine. As I recall he threw it in reverse and increased the throttle to stop it. I'm not sure, but I think reversing a steam engine involves reversing the engine which means the crank throw changes which way it orbits the fly wheel. Steering was different you had to crank the steering wheel about ten revolutions to get the front wheels to turn a few degrees. In case you are wondering what steaming tobacco beds was, It was a big box maybe 8 feet by 8 feet about 6 inches high, on 2 wheels (called a steam pan). it was lowered onto the ground and steam was piped into it. It killed all the weeds and fungus before the tobacco grower planted his tobacco. My Grandfather would go farm to farm selling his services, at about 3 to 5 miles per hour. http://steamtraction.farmcollector.c..._1983_04-1.jpg

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## Anti Federalist

Awesome story, thanks for posting.




> My Father had an Advance Rumely willed to him by my Grandfather. My Grandfather also had a Nichols and Shepard, a Buffalo Pitts and a Case. They used them for farming early on, threshing and so on. In later years they used them for running the silo blower, steaming tobacco beds, running them in parades and steaming sweet corn at local town festivals. Here is a video of one similar to my Father's steam engine tractor, except his had brass bands wrapped around the boiler. The reserve water tank was also mounted in the back along with the coal box.
> 
> 
> I helped load it on a flatbed a couple of times for parades. I steered and my Father operated the engine. As I recall he threw it in reverse and increased the throttle to stop it. I'm not sure, but I think reversing a steam engine involves reversing the engine which means the crank throw changes which way it orbits the fly wheel. Steering was different you had to crank the steering wheel about ten revolutions to get the front wheels to turn a few degrees. In case you are wondering what steaming tobacco beds was, It was a big box maybe 8 feet by 8 feet about 6 inches high, on 2 wheels (called a steam pan). it was lowered onto the ground and steam was piped into it. It killed all the weeds and fungus before the tobacco grower planted his tobacco. My Grandfather would go farm to farm selling his services, at about 3 to 5 miles per hour. http://steamtraction.farmcollector.c..._1983_04-1.jpg

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## buenijo

One way to get high efficiency in a piston steam engine is to use a compounded piston steam engine with steam reheat and heat regeneration. Three cylinders or more is preferable. There are many ways to go about this, but all have the same basic goal: expand high pressure steam through the engine while reheating the steam before it expands into the next cylinder - this boosts temperature (and therefore volume and/or pressure) to increase engine output - then regenerate the excess heat back into the system. Thermodynamically the ideal state of affairs is heating the steam as it moves through the engine such that the steam temperature is never allowed to drop below max, fully expanding the steam down to condenser pressure, then sending the very high temperature but low pressure steam through an air preheater that is able to cool the steam down to saturation, sending the heated air to the furnace, then sending the low pressure saturated steam to the condenser. This is basically what modern steam power plants do to approach 50% net thermal efficiency. There is no physical reason why a piston engine cannot be devised to see similar performance, but it would be a nightmare to actually build something like this. A two cylinder compounded steam engine can see a part load efficiency equal to the peak efficiency of a very good small wood gas engine system (about 20%) while using steam at 500 psig and less than 600F if it were a good engine and made good use of this strategy. It could have all the benefits of a small wood gas engine system with all the advantages of steam power (quiet, wider range of fuel, cleaner combustion, slow moving and long lasting, a near flat efficiency profile, and all heat available at condenser for ease and efficiency in cogeneration). Still, this option is not practical without access to the necessary hardware. For this reason biomass gasification for fueling internal combustion engines is the practical alternative for making use of biomass for cogeneration.

REFRIGERANT BOTTOMING CYCLE: A strategy that has been used in piston steam engine systems of the past was to transfer the heat in the system to a refrigerant part way through the cycle. This boosts the average pressure in the engine. Below a certain steam pressure, the higher friction in a piston engine can lead to diminishing returns. This is why small piston steam engines generally do not expand the steam below a certain value (generally keeping steam pressure well above atmospheric while in the cylinder). Well, this corresponds to a temperature on the order of 250F or higher. What can be done (and has been done) is to use the steam condenser to heat and vaporize a refrigerant under pressure. This high pressure refrigerant can then be used to drive another piston. This keeps cylinder pressures very high to minimize friction losses, and allows for extending engine operation to much lower temperatures. I am aware of this strategy applied to a large stationary piston steam engine power plant that increased overall efficiency by about 50%. Another strategy that was used on the Titanic was to put a low pressure turbine on the exhaust of their compounded piston engines. Unfortunately, small turbines are not generally efficient, especially at low pressure. So, a low power (small) system could use the former strategy to boost efficiency. If anyone is interested to try this, I recommend using a scroll automotive a/c compressor as the refrigerant expander. Remove the discharge reed valve and admit pressurized refrigerant through the unit backwards. This approach would be far simpler than alternatives largely because the compressor is already designed to contain the refrigerant. Also, I have referenced studies that indicate these compressors operate as expanders with reasonably high efficiency. 

In my opinion, a better strategy to increase the efficiency of very small systems is to make full use of the heat from the system for other applications (i.e. space heating, water heating, water pasteurization, water distillation, absorption/adsorption cooling, biomass fuel drying, etc.). For this reason, perhaps the most rational design would be the simplest configuration that achieves good performance. In my opinion, the single-acting uniflow that admits steam with a bash valve or small poppet valve is the best candidate. If supplied with steam on the order of 1000F and on the order of 1000 psi, such a system can achieve 20% net thermal efficiency even with atmospheric exhaust (at 212F) that can be put to efficient use in many heating applications.

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## buenijo

Looks like money is getting thrown at small scale steam power:

http://www.vdg.no/?menuid=16

http://www.vdg.no/index.php?articleid=12

I can't find specifics on the engine, but if an established engine manufacturer is behind this, then it's very promising.

Addendum: This appears to be an organic rankine cycle using n-pentane as the working fluid.

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## presence

> I'm thinking I might try to make a steam engine now.





<br>

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## buenijo

Making a steam engine isn't terribly difficult. Making a useful steam engine would be difficult and expensive. Please consider a charcoal or wood gas engine system instead. You will be surprised how easy it is to make a small charcoal gasifier that can be useful. You can even make it compact enough to power a bicycle and it's efficient... can get 15-20 miles per pound of charcoal on a bike/scooter in city driving and it's possible to supplement the charcoal with biomass like wood pellets or chips to extend the range of the charcoal further.

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## osan

> 


Hey, that almost looks like Kinzers PA.

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## Anti Federalist

Bump.

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## buenijo

Sending the exhaust of a steam engine into a container of a strong hygroscopic salt solution such as sodium hydroxide or calcium chloride will cause the solution temperature to rise. The effect can be strong enough to heat the steam generator used to power the engine itself. In fact, small locomotives have been powered using this principle: https://www.scribd.com/document/4185...ireless-engine . Note that the vessel containing the solution is not pressurized. Rather, the solution surrounds the steam generator tubing that is pressurized. The system is silent during operation and with no emissions. The vessel when heated for regeneration will release the water previous absorbed in the form of superheated steam.

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## luctor-et-emergo

> Making a steam engine isn't terribly difficult. Making a useful steam engine would be difficult and expensive. Please consider a charcoal or wood gas engine system instead. You will be surprised how easy it is to make a small charcoal gasifier that can be useful. You can even make it compact enough to power a bicycle and it's efficient... can get 15-20 miles per pound of charcoal on a bike/scooter in city driving and it's possible to supplement the charcoal with biomass like wood pellets or chips to extend the range of the charcoal further.


I like the idea of a wood fired bike.. I'd love to take the smell of a stove with me. Sadly I don't think I'd get very far without being pulled over  .

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## buenijo

I just considered an interesting configuration for the "caustic soda steam engine". 

SUMMARY: Regenerate the solution (while the engine is running) at a low rate equal to the average system power. This will allow for a much smaller quantity of solution to store energy for transients in engine power while allowing a small, simple, low power furnace.

Heating the solution during engine operation can provide a system with the benefits of a fire tube boiler (high energy storage capacity), but without the disadvantages of a large (and expensive) pressure vessel. Rather, the pressure vessel is a monotube steam generator contained within. So, the system can be heated at a low rate, but provide a store of energy much like a fire tube boiler to take the engine to higher power levels as required. The quantity of solution required would be much smaller, and the concentration can be maintained high for higher steam temperatures and pressures. Also, the superheated steam vented can be used to preheat boiler feed water for higher efficiency. Add a recuperator that uses furnace exhaust gases to preheat combustion air for even better efficiency. 

I can't think of a practical application for this, but any system that otherwise calls for a modest fire tube boiler might be used. It makes sense only where the output of the system is likely to change frequently. A small steam boat might make use of it. As long as the average output required is very low, then the furnace required to support the system can be a low output. This would make it possible to use a small and simple updraft biomass furnace. While not necessarily practical, I think such a system could be fairly simple.

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## buenijo

> I like the idea of a wood fired bike.. I'd love to take the smell of a stove with me. Sadly I don't think I'd get very far without being pulled over  .


In my opinion, the most practical way to fuel a motorcycle (i.e. "bike") with wood is to start by not trying to fuel it 100% with wood. Rather, a small wood gasifier can be used to supplement fuel to the engine. This can increase MPG on gasoline fuel many fold. Here's how: the engine in a road vehicle normally operates at a small fraction of its rated power. Therefore, a small wood gasifier can provide nearly all the fuel during this time. For example, a typical motorcycle requires only about 10 hp to maintain highway speeds on level ground. Therefore, a gasifier need not provide more fuel gas than required to maintain 10 hp. Gasoline fuel can be used during acceleration and hill climbing to boost engine power as required. A smaller gasifier requires a proportionally smaller filter and cooling system as well. Therefore, configuring a bike in this manner could be more practical as compared to the 100% wood gas conversion.

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## buenijo

Engineer775 of YouTube is staring an organic rankine cycle project using an automotive scroll a/c compressor:

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## Lifesoup

> Engineer775 of YouTube is staring an organic rankine cycle project using an automotive scroll a/c compressor:
> 
> http://www.youtube.com/watch?v=roxTv1Xtaps


Interesting....

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## Brian4Liberty

> I live in literally one of the sunniest places on earth and have a 2kw photovoltaic system up and running on my house.  So I am bullish on solar energy.  BUT it has some seroous drawbacks.  The biggest is that it will only produce power during the hours of peak daylight.  So how are you going to power your freezer, lights, ham radio, ac, furnace, whatever from late afternoon to mid-morning?  
> 
> Batteries suck for long-term off-grid purposes.  They are expensive, heavy, toxic, have a limited lifespan, and cannot be easily improvised.
> 
> I have given serious thought to the idea of storing solar energy and the options are not very good.  If you have lots of land with a significant elevation gradient, and plenty of water, you can set up a system that pumps water into a reservoir on the high end of the property using solar energy during the day and then at night drain the water back down to a lower reservoir through a turbine at night.  But I don't have much water.
> 
> You could also use solar to electolyse water, store the hydrogen, then burn it in an internal combustion engine to run a generator.  But there are so many steps in the process it becomes very inefficient.  And hydrogen is a bitch to work with. 
> 
> The best option I have come up with for sunny, dry climates is storing solar energy as thermal energy during the day and then extracting it at night with a heat engine.  For example, you could use solar energy to heat a very large concrete block, solar oven style, during the day and then use multiple Sterling engines to run off the heat contained in the block and turn a generator during the night.  This would be simple and efficient, but fixed in place, and lots of moving parts because of the multiple sterling engines.  And still impacted by cloudy days.


How about compressing air during the day?

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## buenijo

> How about compressing air during the day?


Too many losses, and the energy density of compressed air is too low.

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## Brian4Liberty

> Too many losses, and the energy density of compressed air is too low.


I like the simplicity and chemical safety (nothing toxic, hard to acquire or exceptionally flammable) of the idea. No idea how it compares to other storage options.

Those compressed air vehicles seemed pretty cool.

http://reviews.cnet.com/8301-31346_7...e-air-vehicle/

http://reviews.cnet.com/8301-13746_7-10187871-48.html

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## Brian4Liberty

> Too many losses, and the energy density of compressed air is too low.


The post I responded to had an option of storing energy via water tanks. How does the energy compare with the same size storage tank? (Water vs compressed air).

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## buenijo

> The post I responded to had an option of storing energy via water tanks. How does the energy compare with the same size storage tank? (Water vs compressed air).


Storing appreciable energy in a water tank requires the tank to be highly elevated and/or having a lot of water. The energy stored is proportional to both the mass of water stored and the elevation. So, doubling the elevation would reduce the amount of water required to store a given quantity of energy by half. Generally, this prospect is viable only where one has a large amount of land of varying elevation to provide the required elevation and huge mass of water. I'll give you an idea of how much water is required. One hp is 550 foot pounds per second. If you have an elevation of 100 feet, then 5.5 pounds of water must flow from this elevation per second. Over an hour, that's about 2370 gallons of water. After considering the losses involved, this would net you about one half KWh of electricity (500 watt hours, or 500 watts for one hour). This same electricity is provided by a lead acid battery weighing about 35 pounds, or a lithium iron phosphate battery weighing under 20 pounds.  

Note that the elevation is the main limitation in most cases. If I had more than a few hundred feet to play with, only then would I start to think about it seriously. Compressed air is a better prospect, but even that falls short. In my opinion, the only practical means to store appreciable energy for the production of electricity (assuming individual/residential scale) is (1) a battery, or (2) a fuel (might include biomass such as wood). Heat can be stored in a thermal mass such as water, but without high temperatures any attempt to convert the heat to electricity will be very inefficient.

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## Brian4Liberty

> Storing appreciable energy in a water tank requires the tank to be highly elevated and/or having a lot of water. The energy stored is proportional to both the mass of water stored and the elevation. So, doubling the elevation would reduce the amount of water required to store a given quantity of energy by half. Generally, this prospect is viable only where one has a large amount of land of varying elevation to provide the required elevation and huge mass of water. I'll give you an idea of how much water is required. One hp is 550 foot pounds per second. If you have an elevation of 100 feet, then 5.5 pounds of water must flow from this elevation per second. Over an hour, that's about 2370 gallons of water. After considering the losses involved, this would net you about one half KWh of electricity (500 watt hours, or 500 watts for one hour). This same electricity is provided by a lead acid battery weighing about 35 pounds, or a lithium iron phosphate battery weighing under 20 pounds.  
> 
> Note that the elevation is the main limitation in most cases. If I had more than a few hundred feet to play with, only then would I start to think about it seriously. Compressed air is a better prospect, but even that falls short. In my opinion, the only practical means to store appreciable energy for the production of electricity (assuming individual/residential scale) is (1) a battery, or (2) a fuel (might include biomass such as wood). Heat can be stored in a thermal mass such as water, but without high temperatures any attempt to convert the heat to electricity will be very inefficient.


Yeah, I wouldn't try to pump water uphill as a way to store the energy for later. Plus there is the size requirements as you pointed out. And you can't compress water.

Water and an appropriate property? All you just need is a year-round stream or waterfall.

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## buenijo

> Water and an appropriate property? All you just need is a year-round stream or waterfall.


Or you could say property with appropriate water,  .

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## buenijo

I discuss an alternative means to distill water efficiently using heat that is cascaded in multiple stages. I am making this post to clarify the configuration as I believe it has potential for some applications... and it's interesting.

The simplest way to introduce the idea is to provide a straightforward example. Consider a pressure cooker. Fill the pressure cooker with water that you wish to distill. Now, place a nonpressurized vessel next to the pressure cooker, and fill this vessel with water from the same source. Place a large copper tubing coil at the bottom of this vessel. The top of this tubing coil is connected to the top of the pressure cooker. The bottom of the coil is connected to the bottom of the vessel via a needle valve (or relief valve). This needle valve is throttled to keep sufficient pressure in the pressure cooker (high enough for high temperature, but not so high that the pressure cooker relief valve lifts) - or the relief valve at the end of the tube is set to lift at the correct pressure.

Now apply heat to the pressure cooker. The water in the pressure cooker will increase in temperature and steam will finally form and pressurize the vessel. The steam will fill the copper tubing. Since the temperature of the steam in the pressure cooker is well above 212F, then the water surrounding the copper tubing coil will boil. The steam in the copper tubing will condense to water in the process, and this water will drain from the end of the tube via the valve provided. The steam released from the nonpressurized vessel can be directed through a condenser, and this water can also be collected. Therefore, a source of heat that would have normally produced x amount of distilled water can be made to produce nearly 2x amount of distilled water through "staging". For efficiency, the hot condensate that leaves the copper tube should be used to preheat cool water used to replenish the water into the system.

Consider that a system can be designed for space heating purposes that also generates distilled water at a high rate. Using 2 or 3 stages, a furnace could be used to heat the first stage, then generate steam at the final stage that can be used for heating applications. This can not only purify a local water source, but also allow for reprocessing water that is otherwise discarded as waste (recycling water through distillation). 

NOTE: Rain water catchment and storage for water in the remote/off grid setting is the most practical alternative I've seen for securing water in a remote setting (for most regions). Still, this distillation approach is interesting, and might be practical in some settings.

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## buenijo

http://www.internationalsteam.co.uk/...m/modern50.htm

Interesting discussion on work done during the 1900's to increase the performance of steam locomotives. Most of the advances seems to have been achieved after Diesel took over the industry. Evidence suggests that the improved efficiency and lower labor costs of a modern steam locomotive, along with the much lower fuel costs of coal vs. Diesel, would make modern steam more economical. Advancements that made the most contributions include clean and efficient combustion of coal fuel using gasification, higher steam temperature and higher pressure with both compounding and heat regeneration to increase thermal efficiency, low friction with improved seals and use of roller bearings, superior insulation, streamlined steam exhaust, and advanced boiler chemistry. The average overall efficiency of steam locomotives in the U.S. was a paltry 6%. Modern locomotives actually constructed and operated have shown 14% overall efficiency. Third generation systems are projected to see 21% thermal efficiency. With steam condensing, the system is project to achieve 27% efficiency. 

I suspect that steam made little advancement over a long period quite simply because there was no competition. It was not until Diesel took over the industry that any effort was made to optimize the steam locomotive, and the funding available was very limited. 

NOTE: See the description of the new fire box design for modern coal fired locomotive. A minor modification was necessary to achieve clean combustion. Anyone who has made even a brief study of solid fuel gasification could have done this. I am somewhat bewildered that this was not done far sooner (?). The only explanation I can arrive at is that people tend to get stuck in a way of doing things (if it ain't broke, then don't fix it), and a corporate mentality might have contributed. Most people including mechanics and engineers rarely challenge the status quo. The only changes that were made were to (1) make a deep coal bed, (2) provide steam with the intake air, (3) provide most of the air for combustion via a secondary path (not through the coal bed). Before, 90% of the air was forced through the coal bed. Gasification took place, but most of the air did not react with the charcoal. It combusted any combustible gases later on in the fire box, but forcing air at such a high rate entrained particles and led to dirty exhaust. Also, some conditions would lead to insufficient air for full combustion, and this would cause smoky exhaust. Not providing the excess air through the coal bed might have led to clinker formation on the grate where high temperatures cause ash to melt. Excess air would have taken the temperature down to prevent this clinker formation (but caused the other problems). Adding steam to the primary air helps to moderate the temperatures, and the steam reacts with the hot carbon to make more CO and H2 fuel gas. The final result is that air moves through the fuel bed at 1/3 the rate as before, and there is always excess air provided for full combustion... so particulates are not entrained with the air and there is no smoke... the system also gets higher efficiency. Actually, the combination of gasifying the coal and doubling the thermal efficiency means the actual rate at which primary air was forced through the coal bed was on the order of 6 times less than before. This is why a modern coal fired steam locomotive would be a great deal cleaner then the old systems.

I have done testing with a simple updraft biomass gasifier furnace. It is EASY to control these units with respect to firing rate. Containing the fuel in a well insulated base allows for controlling the rate of combustible gas formation by simply controlling the rate at which primary air (the air moving through the fuel bed) is admitted. For full combustion, simply add sufficient secondary air to eliminate smoke on exhaust. I mean, it really is simple, and my experience with this has me shaking my head about how much smoke and soot was thrown out of old steam locomotives unnecessarily. The low thermal efficiency of the engines were also a problem, and perhaps forcing air at such a high rate was done just to get the desired power (soot be damned). 

Hmmm... I wonder what it takes for an individual to buy coal in bulk? I have no qualms at all about running an off grid home on a coal fired steam engine. I think I should build such a system optimized for coal fuel and christen it the "Al Gore", .

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## buenijo

A recent quote at a coal mine in Kansas showed $65 per ton of bituminous coal for local pick up! At that price an efficient steam engine that made full use of the waste heat could power a modest off grid home for about $1 in fuel costs per day. Such a system could use coal or wood, and any dry biomass that can feed by gravity down the hopper to the hearth. The configuration I am considering is an updraft gasifier furnace with a grate and ash pit. Primary air is forced, and secondary air is by draft. Any fuel that gets into the insulated hearth region just above the grate will be pyrolysed, and any carbon remaining on the grate will be consumed by the air entering the system below the grate. Ash falls through the grate.

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## buenijo

Good discussion of modern steam locomotives. 

http://www.csrail.org/index.php/rese...steam-advances

Again, it's fascinating to me how the performance of steam locomotives can be improved so dramatically using seemingly simple technologies. The changes to traditional steam locomotives that have been demonstrated include a full doubling of overall efficiency, efficient and near smoke free combustion of coal, a doubling of power/weight, and a fantastic reduction of boiler maintenance costs. The boiler water treatment increases boiler life to equal the operating life of the locomotive. 

The site also mentions the use of torrefied biomass to generate "biocoal". This is an interesting prospect. The heat released in the process of making the product can be put to use in stationary applications. The charcoal that remains has a lower ash, sulfur, and heavy metal composition than coal.

Good link on the topic: http://www.trainweb.org/tusp/porta.html

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## buenijo

http://www.catskillarchive.com/rrextra/chapt25.Html

Excellent discussion of the physics of steam engines, and without a lot of technical jargon.

NOTE: I like the way this discussion describes how steam at higher pressure allows for higher efficiency steam engines. Consider a cylinder that admits 100 psi steam with 50% cutoff for 2 fold expansion. The average cylinder pressure is roughly 85 psi. Now consider the admission of 200 psi steam with 25% cutoff for 4 fold expansion. The average cylinder pressure is roughly 120 psi. While we used half the volume of steam in the second case, we must note that steam at 200 psi has twice the mass and energy as steam at 100 psi. Therefore, the amount of steam energy used in both cases is roughly equal. However, we got nearly 50% more work in the second case, which implies that efficiency increases by nearly 50%. Now, there are other dynamics at play that make this a simplistic conclusion - but, it certainly increases efficiency significantly. The same effect can be had in principle by using lower pressure steam with higher expansion ratios. However, the mean effective pressure starts to drop quickly, and this allows friction to represent an increasing proportion of the work load (hence, efficiency increases are limited there). Note also that the temperature difference of the steam as it expands in the cylinder can also be used as a proxy for the efficiency. Steam temperature falls at it expands (and does work), and this drop in temperature is proportional to the work done by the steam on the piston and crank. Of course, there are many other variables to consider, but this correlation is important to note (correlation between increased expansion ratio and larger temperature difference - and increased efficiency - ever heard of the Carnot efficiency of a heat engine?). See post #179 for a continued discussion on the efficiency of piston steam engine systems.

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## buenijo

http://reneweconomy.com.au/2013/retu...or-solar-34662
http://www.terrajoulecorp.com/unexpe.../how-it-works/
http://www.terrajoulecorp.com/unexpe...hat-it-is-not/

I've been aware of this for a while. I like the idea. In my opinion, it's not suitable for micro scale CHP, but I think it has promise for medium scale installations - and this seems to be the target market. 

The way I understand this system based on what I read, and extrapolating from my knowledge of steam power, is that a two cylinder compounded engine is used. These systems provide steam at high pressure to a small cylinder where the steam expands, then exhausts the lower pressure steam to a larger cylinder for additional expansion before finally exhausting to the condenser. The system here uses Skinner unaflow engines that were manufactured as late as the 1940's. These engines had a reputation for high efficiency, and extreme reliability. During the day when the solar concentrators are generating high pressure steam, then the steam is sent to the high pressure cylinder. The larger low pressure cylinder is not used when additional energy storage is desired. Rather, the steam is exhausted to a large insulated steel pressure vessel filled with water. The steam exhaust raises the temperature and pressure of the water. When sufficient energy storage is achieved, or whenever higher power is desired, then the low pressure cylinder may be used in addition to the high pressure cylinder. When solar is not available (such as at night), then high pressure steam is not available, and the system draws low pressure steam from the pressure vessel by flashing water to steam to drive the low pressure cylinder. Turns out that there is negligible loss of efficiency by going this route. That is, while the engine is most efficient when full expansion is achieved with both cylinders, the energy otherwise used to drive the low pressure cylinder is stored in the pressure vessel for later use. The system achieves 24 hour power generation from solar without batteries, and the storage system is the most cost effective I've yet seen. 

The discussions on the web site about the benefits of piston steam engines in lower power ranges are spot on. Turbines are great for high power and constant output. Below a certain power, the piston steam engine is more efficient, and the efficiency of piston steam engines vary little as the power varies. So, anything below about a megawatt favors the piston steam engine.

http://www.greentechmedia.com/articl...Energy-Storage (See the comments by the CEO of the company in the COMMENTS section of the page)

Turns out that the steam pressures and temperatures achieved with this system, along with using irrigation water pumped by the system to cool the condenser, will allow for good efficiency. The CEO claims 30% cycle efficiency with 70% concentrator efficiency, and this would allow for 20% overall conversion of solar energy to work. More important, the efficiency of the system is not important - it's all about COST. In my opinion, this is where this system shines. I think it's brilliant.

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## osan

> The discussions on the web site about the benefits of piston steam engines in lower power ranges are spot on. Turbines are great for high power and constant output. Below a certain power, the piston steam engine is more efficient, and the efficiency of piston steam engines vary little as the power varies. So, anything below about a megawatt favors the piston steam engine.


This is largely because turbines are efficient in only a comparatively very narrow range of operating speeds.  At lower speeds the slip losses are large and lots of usable energy goes out the pipe.  The Tesla turbine is perhaps the worst in this respect having miserable startup characteristics and is well served by a vein-type starter turbine to get it going.  Because piston engines are perfectly sealed for all practical purposes, the minimal effective energy charge to produce power is far smaller than for turbines, which leak tons of energy until they come up to snuff.  Because of the good seal at all operating speeds, piston engines run with similar efficiencies over a very broad operating range.  Turn them on and off often... no big deal when compared with turbines, all else equal.  In this they are far more flexible, the price being mechanical complexity and the attendant reliability reductions.

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## buenijo

> This is largely because turbines are efficient in only a comparatively very narrow range of operating speeds.  At lower speeds the slip losses are large and lots of usable energy goes out the pipe.  The Tesla turbine is perhaps the worst in this respect having miserable startup characteristics and is well served by a vein-type starter turbine to get it going.  Because piston engines are perfectly sealed for all practical purposes, the minimal effective energy charge to produce power is far smaller than for turbines, which leak tons of energy until they come up to snuff.  Because of the good seal at all operating speeds, piston engines run with similar efficiencies over a very broad operating range.  Turn them on and off often... no big deal when compared with turbines, all else equal.  In this they are far more flexible, the price being mechanical complexity and the attendant reliability reductions.


Yes, very good description of the problem. The quality of steam engines you described shows itself as a flat torque profile at all speeds. The qualities of the turbine are great for very large scale systems that run one or more large turbines to provide a base load for the grid. This is good for centralized power. The qualities of the piston steam engine are ideal for micro to medium scale distributed energy systems.

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## buenijo

EXCELLENT reference on piston steam engines: "Steam Engine Principles and Practice"

https://archive.org/stream/steamengi...ge/n0/mode/1up

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## buenijo

The book I referenced in the previous post has very good discussions about how to optimize efficiency in piston steam engines. While I didn't learn much from the book, the information available took me a while to gather piecemeal from other sources. So, this is a very good single reference source for those who wish to learn the subject of piston steam engines - probably the single best source I've yet seen. 

Consider the simple counterflow, double-acting, piston steam engine with slide valve that uses saturated or very slightly superheated steam at modest pressures. These kind of engines include the engine shown in the original post of this thread, the Mike Brown engine, and the engines made by Tiny Tech India that were discussed earlier in this thread. A major loss in these kinds of engines is condensation of steam in the cylinder. The steam exhausted from the cylinder moves through the same passageways through which the high pressure steam is admitted during the power stroke. What happens is this low temperature steam cools the metal. So, the hot incoming steam reheats it, and during the process a lot of the incoming steam is condensed. Well, this means more steam is consumed to achieve the same pressure effect - more steam means more heat for the same effect, and therefore lower efficiency. Furthermore, some of the condensation in the cylinder will flash to steam when the valve opens up the cylinder to the lower exhaust pressure, and this can give the cylinder head a particularly thorough cooling. This tends to aggravate the problem of incoming steam condensing. For this reason, putting a condenser on these simple engines with high vacuum does not increase efficiency all that much since the very low vacuum will flash the condensate effectively and cool the cylinder head. It's a catch 22 - one can try to boost the low efficiency by decreasing the back pressure on the engine with a condenser vacuum, but the condensate in the cylinder flashes to cool the cylinder head. More incoming steam condenses, and this increases steam consumption (and therefore dampens any gain in efficiency due to vacuum). It might boost efficiency, but it's generally not worth the additional hardware for these simple engines. For this reason the simple engines were used when steam heating was desired since low thermal efficiency doesn't matter much here. A small engine of this type typically sees a thermal efficiency of around 6% not including boiler losses. So, even a good small scale steam engine system using this engine would see an overall efficiency of 4-5% at best. This isn't so bad if the primary purpose is something like space heating a home, but don't expect to generate much electricity or shaft power. Larger engines of the same design are often better since the ratio of cylinder volume to surface area lessens condensation, and lessens cylinder blow by/friction losses/and thermal losses from the cylinder. Simple counterflow engines with a different valve mechanism can improve efficiency. One example is the Corliss engine. By using separate exhaust and inlet valves the cooling effect does not cause so much condensation of the incoming steam, and efficiency improves. If one desires higher efficiency, then consider a compounded engine and/or a uniflow. 

The compounded engine increases efficiency by increasing expansion - or should I say by allowing a given quantity of steam admitted into the engine to achieve high expansion. Good simple engines can boost efficiency with expansion (done by shortening the valve cutoff), but a small simple counterflow engine can't tolerate much expansion. Even the larger engines like locomotive engines didn't allow for more than about 4 fold expansion in a single cylinder. Saturated steam shows some condensation as expansion takes place, and the combination of expansion and thermal losses from the cylinder (especially cylinder head cooling) increases condensation and negates a lot of the gains. Superheating the steam helps a great deal. However, this is not good for slide valves that tend to warp with high superheat and see their lubrication compromised. All these put a cap on the expansion (and hence efficiency) possible in a simple counterflow engine. If expansion is done in two or more cylinders (as in the compounded engine), then the pressure seen in the first cylinder on exhaust is not nearly so low as in the single cylinder version. So, the steam exhausted from the first cylinder isn't at such a low temperature. The cylinder head and passageways in the first cylinder don't get cooled so much, and condensation that may flash to steam on the lower pressure is carried over to the second cylinder to do work. The lower differential pressure across the pistons and valves also lessens leakage, and the forces are distributed over the crank shaft evenly in many designs for lower peak forces on the bearings which raises mechanical efficiency. In short, the compounded engine is a lot more efficient. These dynamics make it possible to expand steam over a much wider range and see higher efficiency. The book I referenced has a lot of data on the efficiency of these engines, and the compounded engine often shows twice the efficiency of the simple engine when using the same steam source. These engines benefit a great deal from a condenser vacuum, yet the simple engines do not gain much in efficiency with condenser vacuum as discussed previously. Throw in steam reheat and regeneration, and the efficiency of a compounded engine can be remarkable. One multi compounded engine mentioned in the book showed a thermal efficiency of 27% using steam at only 600F - it did this by reheating the steam exhausted from each cylinder before entering the next, and then finally regenerating the added heat back into the system after the superheated steam was finally exhausted from the last cylinder. Without this complicated reheat and regeneration scheme, a large compounded engine using saturated steam under 200 psi and with condenser vacuum can show an efficiency of 20% (not including thermal losses from the boiler). This is pretty amazing. 

The uniflow engine improves efficiency by exhausting the steam through ports in the cylinder wall. This lessens the cooling of the cylinder head, and therefore lessens the condensation or cooling of incoming steam. For this reason, the uniflow does well on a condenser vacuum. Using a vacuum also helps to exhaust the steam, and indirectly allows for higher expansion of the steam. For best results, the uniflow requires a condenser at high vacuum. However, they can be run exhausted to atmosphere, and the gain in efficiency by moving to a vacuum condenser increases by only about 20% (all else equal). Also, uniflow engines generally use poppet valves that can tolerate higher steam temperatures. The combination of higher steam temperatures and higher expansion allow for the uniflow to see significantly higher efficiencies than simple engines. One engine noted in the book showed a thermal efficiency of about 30% with steam at 461 psi and 1000F. The White Cliffs uniflow engine using bash valves showed 23% with steam at 600 psi and 800F (boiler losses not included), and exhausting to a condenser at 160F. Ideally the uniflow engine shows very high compression of the residual steam. In fact, the ideal system would recompress the steam up to the boiler pressure. The intake valve would then open and let in steam from the boiler for a short time, then the valve would abruptly shut and allow the steam to see high expansion. The exhaust ports would then be uncovered by the piston, and the cycle would continue again with recompression. It's interesting to me how this relatively simple system can show impressive efficiency. Good compounded engines were generally more efficient than a uniflow using the same steam source, but a single cylinder uniflow is simpler. There are highly efficient engines that use a combination of compounding and uniflow exhaust (see Skinner Universal Uniflow engines). These have shown nearly 30% efficiency with steam at about 600F and exhausting to a high vacuum (figure does not include boiler losses). 

Since my primary interest in steam power is biomass-fueled micro scale combined heat and power, I have considered that the most practical way to make use of steam power would be a single acting uniflow tuned for a net thermal efficiency on the order of 10-15%. I think the bump/bash valve is the simplest way to do this. Much higher efficiency than this would be difficult and likely require excessive temps or excessive expansion ratios. Since heat is the most desirable product in many settings, then there is little need for very high efficiency in that case. However, I believe 10-15% can be had with a simple system. In my opinion, the main design consideration should not be high thermal efficiency, but the emphasis should be on simplicity, reliability, making good use of the heat from the steam exhaust, a modest speed and constant low output, and the ability for the system to be fully serviced by the end user. For example, every wear component should be easily accessed and replaced with readily available and inexpensive components, and the base system should be extremely rugged. 

http://kimmelsteam.com/docs/Cylinder...pp203-4red.pdf

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## osan

Speaking of long term energy storage, I cannot help but wonder whatever happened with IBM's nano capacitor technology.  IIRC, using folded carbon nanotubes as a dielectric, the surface area of the conductors is absolutely enormous, thereby greatly increasing the charge density such that they can be used as batteries.  I remember the press releases were all going on about how this was going to revolutionize battery technology... electric cars that can go 500 or more miles on a charge and recharge in seconds, cell phones needing no charging for weeks on end, and so on.

Since than I have heard nothing about it, which is a damned shame.  Way back in the pre-civil war days when I was an engineering student at UC Davis, I'd wondered about capacitors as batteries.  As it turned out, charge densities were too low, but this new tech is supposed to be well on the way to solving that problem.

What happened to it?  Take a look at this:




And this:




The best part of all this: you can do it at home.  No $#@!.  All you need is a graphite source, a few chemicals, and a CD drive.

This could be a real  improvement to steam generators.  Imagine having a bank of these batteries that would store many coulombs of charge, perhaps enough to run your household for, say, a month.  You fire up your steam rig, perhaps here a turbine would be the way to go for efficiency's sake, and in a few hours your storage is topped off and you can shut it down for the next 30 days.

I am wondering why we're not hearing more about this and someone, somewhere, in the process of designing practical graphene batteries for manufacture.

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## buenijo

Osan, I am aware of that work. I suspect the media took it and hyped it up a bit. Perhaps there will be something practical to come out of the work, but I bet it'll be a while before we see anything. If a cost effective and highly energy dense battery were to be produced, and with the ability to be fast charging, then I suspect this would be a boon primarily for photovoltaics in the off grid setting and EV's... at least, these are what I would use it for. One reason I consider seriously the prospect for a micro scale combined heat and power steam system is the possibility for such a system to be configured to operate for long periods at low output, and this would eliminate the need for a high capacity battery system. Come up with an inexpensive super battery that lasts as long as the PV panels, and I would focus on PV as a primary source of electricity in the off grid setting. However, it's also true that a properly configured micro scale combined heat and power system can use a fuel in a very highly efficient manner - and that's also a very attractive prospect. Consider that as good as these batteries get with respect to energy density, they're never going to approach the energy density of a fuel source - including biomass.

Also, speaking of long term energy storage, I believe I posted on using desiccants for thermal storage. One example is zeolite which has the ability to store heat indirectly with an energy density four times better than water (at atmospheric pressure) by mass, and twice as good by volume. Solar heated air has been shown to regenerate such desiccants effectively. The desiccant generates heat as it adsorbs water vapor into its internal porous structure, and this heat can be used for heating applications. It can also dry air for use in evaporate cooling. If/when solar insolation may be insufficient, then a micro heat engine might be used to simultaneously recharge the graphene capacitor and while regenerating the zeolite desiccant.

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## buenijo

Check out this very sophisticated micro steam engine project. While not useful due to the very low power, it has a lot of interesting features and it appears to be a high quality piece of work. Clearly Dan is very talented.




The most interesting feature to me is the way he devised an exhaust valve in the piston to eliminate compression. I have seen engines described that do this, but this is the first time I've seen one incorporated with a bash valve intake valve. The bash valve seals steam from entering the piston until an extension on the piston taps it open on the up stroke to let in a charge of high pressure steam. These are generally used only with uniflow piston steam engines where the steam is exhausted from the cylinder when the piston uncovers one or more ports in the cylinder wall. This engine in the link includes a valve in the piston itself to relieve compression. Otherwise, the residual steam in the cylinder would be recompressed in the cylinder head. This recompression is favorable thermodynamically since it helps to reheat the cylinder before admitting a fresh charge of steam. However, if one desires to maintain a high condenser pressure, then I believe this approach is a very good idea. Otherwise, the higher exhaust steam pressure will not allow for high compression as the pressure will rise so high that sufficient steam cannot be admitted through the intake valve. On the exhaust valve used in this system, the steam pressure in the cylinder keeps the valve shut during the power stroke. When the exhaust port in the cylinder is uncovered, then there is no more differential pressure across the piston. This allows a small spring to open the valve to relieve the recompression. An extension on top of the valve serves to tap open the bash valve, but the exhaust valve gets reseated before the intake valve opens. 

On the electronic control of the admission valve, it seems he is holding the inlet valve open by a magnetic field after the the piston unseats the valve. I've seen mechanical systems that do this by providing an adjustable stop on the ball that limits its travel. If the stop is backed off, then the ball can get tapped open a bit more and let in steam for a longer period. If the stop is close to the ball, then the ball reseats more quickly. This mechanical approach has limits that would be overcome by the electronic approach. I think the electronic approach here is interesting and has potential for systems for use in a highly variable output engine (like a constant speed generator or automotive application). Myself, I am interested only in a constant speed system that maintains a low output - I would use DC or a small battery and inverter system for AC power as this is just so much simpler.

ADDENDUM: I came upon this excellent description of this engine: http://www.kimmelsteam.com/gelbart-uniflow.html

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## buenijo

Home made small steam tractor, wood fired:

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## buenijo

Very nice hobby steam engine set up: 




Scale this up about 10 fold and fuel with wood, then it might be useful rather than just pretty! Seriously though, I am impressed. It's a good piece of work. Also, this is large by model steam standards. The engine is rated for 1/4 hp.

The guy has an awesome web site!: http://rcdon.com/index.html

Steam project details: http://rcdon.com/html/6ci_steam_engine_project.html

NOTE: I contacted this individual for some clarification on his system. He is using Teflon compression packing to seal the piston. This along with graphite based packing products is what I'll be trying for my future project. He says it seals very well. He reports that he has only 25 hours on the engine so far, but it still runs as new. He speculates that he will get well over 1000 hours on the seals. Note that Teflon packing generally has a temperature rating of about 500F. The temperature of 100 psi saturated steam is about 330F. However, also note that the piston seal is in contact with the cylinder wall that will be maintained at a temperature roughly equal to the mean between steam generator temp and condenser temps. So, this suggests that Teflon can be used with steam at much higher temperatures. Also, I believe he is using Teflon also to seal the piston valves. This would put a hard limit on the steam temps as the valve sees peak steam temperature. However, poppet valves and bash valves require no such seals.  

ADDENDUM: The owner reports that this engine requires oil lubrication. However, he notes that there is some metal to metal contact in the piston valve. Also, without oil, the cylinder that is not a smooth bore would damage a soft packing material. He didn't specify on this particular cylinder. If one desired to experiment with sealing a steam cylinder without using oil lubrication, then it seems reasonable to start with a smooth bore cylinder (like a hydraulic cylinder). Finally, oil is also useful for protecting metal from corrosion, so if one desired to experiment with doing away with oil lubrication, then it would be necessary to keep a super tight system free of air (fully condensing with good seals).

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## buenijo

http://cozincmtusa.com/home

Interesting site maintained by a small group dedicated to developing a modern highly efficient steam automobile engine. They're focused on a compounded piston engine with reheat and heat regeneration. Solid information. NOTE: I may have listed this previously.

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## buenijo

Articles discussing the 1970's experimental SES automotive steam system: 

http://modernsteampower.wordpress.co...-dodge-monaco/
http://www.steamcar.net/jakuba-1.html
http://kimmelsteam.com/dodge-monaco.html
http://kimmelsteam.com/ses.html

NOTE: I posted this for interest only. The system developed was doomed to fail mainly because it had no hope of achieving sufficiently high fuel economy or sufficiently high power/weight.

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## buenijo

Possibly the single best web site for steam engine education: http://www.kimmelsteam.com/

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## buenijo

A few interesting videos I came upon:

http://www.youtube.com/watch?v=GPUlnqlWt7U

http://www.youtube.com/watch?v=H4i2nYZUBzo

http://www.youtube.com/watch?v=VbMBZNsiGcA

http://www.youtube.com/watch?v=XsOWB_fzrdY

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## buenijo

www.slamvalvemotor.com

This design allows for converting an air compressor or small piston engine to a steam expander. The only problem I have is the efficiency claims made on the web site. It is claimed that this engine will achieve more than 20% thermal efficiency with saturated steam at 405F and exhausting to a condenser at 160F. Well, basically, this is nonsense. In fact, the figure is greater than Rankine cycle efficiency. Other than this BS claim, the system is very clever. The ability to retrofit existing cast iron air compressor units that are low cost is a very good idea. Furthermore, the retrofit requires nothing beyond installing a new compressor head and plumbing the steam supply and exhaust lines to the head.  A cylinder head is provided containing an intake valve and an exhaust valve. This head can be bolted onto existing air compressor units. The valves are made of curved pieces of flat spring steel that seal ports. The intake valve spring tension acts to unseat the valve, but it's kept shut with boiler pressure. The exhaust valve spring tension also acts to unseat the valve, but it's kept shut with cylinder pressure. 

The intake valve is popped open by a small extension on the piston, and this lets in a charge of steam. The exhaust valve shuts as cylinder pressure builds. The piston moves down. Now, cylinder volume increases at an accelerating rate from 0 to 90 degrees past top dead center, and at a certain point corresponding to about 30-45 degrees past top dead center (according to the site) the boiler pressure will force the intake valve shut. There is a control rod on top of the intake valve to control how far it will open, and just barely letting the valve open will make it shut sooner since cylinder pressure will decrease sooner as the piston moves past TDC under this condition (since the admission of steam to the cylinder is restricted by this process). Once the valve shuts then the steam expands to force the piston thereby providing a power stroke.

Near the end of stroke a port in the cylinder relieves cylinder pressure. Without cylinder pressure to seat the exhaust valve, then it springs open and stays open to relieve pressure during the exhaust stroke. It's possible to set the spring tension so that a port is not required since the cylinder pressure will fall as the steam expands. This approach has been called a "decompression" valve in other designs. In my opinion, a superior design would have an extension on the piston (perhaps even a small spring) seat the exhaust valve just before the inlet valve is opened. 

http://www.youtube.com/watch?v=yaMryydpIhs

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## buenijo

www.biosteamengine.com

I don't know anything about their operation. It is clear that the design of the engines is primitive. However, the machine work looks good, and the design is simple, which I like. If anyone finds information on the product, then please post it here.

ADDENDUM: Site appears to be dead.

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## buenijo

http://kimmelsteam.com/docs/Vision%20essay.pdf

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## buenijo

Info on the Pritchard steam engines: 

http://kimmelsteam.com/pritchard.html

Details on the steam car conversion (Ford Falcon): While not particularly fuel efficient at just under 20 mpg U.S. (on kerosene), the city mileage was likely on par with some modern conventional gas cars in some settings (NOTE: a later version showed 22.5 mpg U.S. at 50 mph). The basic design of the system is simple and would likely achieve long operating life. There was no transmission and no clutch. Emissions achieved was comparable to modern vehicles, yet with no pollution control hardware such as catalytic converters and computer controlled ignition systems. The wide fuel capacity of such a vehicle cannot be matched by internal combustion systems - and emissions were low on start up which is not the case with internal combustion cars before the catalytic converter warms up. While not listed in the following links, I understand the steam temperature was limited to 750F to support conventional oil lubrication. Pressure was 1200-1400 psi. Cutoff was 14%, which corresponds to a very low expansion ratio. In short, this engine system was not designed primarily for high efficiency. Overall net thermal efficiency was probably on the order of 15%. Note the use of a steam exhaust motor to drive the condenser fan and water feed pump (an elegant idea). 

http://kimmelsteam.com/images/Pritch...s%20letter.jpg 

http://kimmelsteam.com/images/Pritch...tisment106.jpg

http://www.linux-host.org/energy/spritch.htm

Description of the stationary unit currently in development: 

http://uniflowpower.com/technology/u...generator.aspx

Interesting forum thread started by Ted Pritchard shortly before his death:

http://steamautomobile.com/ForuM/read.php?1,1528,page=1

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## buenijo

Popular Science article on the Carter steam car:

http://books.google.com/books?id=Rke...0WORKS&f=false

SACA article on the system (written by Jay Carter):

http://www.steamautomobile.com/archi...v17n3.CV01.pdf (295 lbs for the complete 90 hp automotive system! - not including required transmission, a conventional automotive unit).

NOTE: The Carter system deviates from previous steam engine design in many ways. One way that is particularly interesting is the control of the steam generator. The steam generator is particularly small with the complete unit (tubing, casing, insulation, fuel delivery, blower fan, and controls) all well under 100 lbs - and compact. The car is not accelerated by forcing a steam throttle valve or controlling a cam system to vary steam cutoff. Rather, when the accelerator pedal is depressed, then the air/fuel is admitted to the burner at a higher rate. This increases steam pressure, and the response is acceptable because there is a relatively low mass of steam generator tubing, a low mass of water/steam contained within the tubes, and a high surface area/volume in the tubing. Adding heat increases the pressure and this increases engine torque. Steam temperature is moderated by controlling the water pumping rate. This is similar in many respects to previous systems, but the absence of a throttle valve makes it quite different. Carter's engine uses bump valves and a manual transmission with clutch. So, the engine idles when at a stop. In many ways the Carter configuration is simpler than all others - and it achieved the best results to date (mid 1970's), and possibly ever.

http://ntrs.nasa.gov/archive/nasa/ca...9810021983.pdf (starting on page 11 is a description of Jay Carter's third generation steam engine used in an experimental solar thermal power generation set up). This discussion sheds some light on how the pistons were lubricated in this system with the comment "Toward the end of each stroke oil is injected directly onto the piston rings to minimize wear and leakage around the rings." Jay Carter notes in a discussion elsewhere that oil is pumped at a high rate to lubricate the engine - on the order of one quart of oil every ten minutes as I recall. Of course, oil must be wholly free of detergents to prevent emulsification with water. Also, I understand a synthetic oil was used for the system. (see these as well: http://ntrs.nasa.gov/archive/nasa/ca...9800011332.pdf, http://pdf.usaid.gov/pdf_docs/PNAAX001.pdf).

The Carter engine is relatively simple and compact (especially compared to high efficiency Stirling engines and sophisticated micro turbines). Yet, in actual tests it was able to generate electricity delivered to the grid at an efficiency of 20% (everything accounted for except the efficiency of the concentrator - that is, 20% of the the heat delivered to the working fluid water/steam was converted to grid quality electricity, and the electricity required to run the auxiliary systems were deducted from the output to provide a net figure) - and the exhaust steam was atmospheric (212F).

http://latimesblogs.latimes.com/.a/6...b186970b-500wi

This is a good basic description of how a centrifugal oil/water separator works.

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## buenijo

The graph shows the efficiency of typical automotive gas and diesel engines as they vary over their power range, and at 50% max rpm which is typical of actual driving conditions. Note that the "Bourque engine" is a sophisticated modern piston steam engine design proposed by mechanical engineer Dr. Robert Bourque (http://www.newsteamengine.com/). The purpose of presenting this is not to introduce his engine, but to illustrate how the efficiency of conventional automotive engines vary significantly over their power range (especially gas engines). Diesel is roughly 7.08 lbm/gal (U.S.) with about 128,500 btu/gal, and gasoline is roughly 6.15 lbm/gal (U.S.) with about 116,000 btu/gal. There are about 2.2 pounds in a Kg. 

The efficiency of the 1.6 liter gas engine over the Normal Operating Range shown varies from 15.2% to 25.5% with a mean value in the low 20's%. The peak efficiency of this engine shown by the graph corresponds to 29.5%. Note that the efficiency drops dramatically at outputs below the Normal Operating Range.

The net thermal efficiency of historical steam cars were as follows: Stanley Steamer (6-8%), White (10-12%), Doble (10-12%), Pritchard (12-15%) - (although, note that the White and Doble systems were capable of 14% overall efficiency at peak output - *). The Stanley saw about 8-10 mpg on kerosene (*). The Doble saw about 10-14 mpg on kerosene and was a very heavy automobile at 6000 pounds (one first hand account claims 13 mpg on highway on gasoline fuel for a restored Doble E series in good running condition). The peak steam temperature to the expander in all cases here were under 800F. Furthermore, these engine systems saw high thermal losses due to poor insulation, poor heat exchange, and distributing steam a distance from a steam generator to the expander (except the Pritchard unit that put the expander right next to the steam generator and did a good job of insulation). Kerosene shows about 124,000 btu per U.S. gallon (lower heating value). My research shows that the Pritchard steam car (converted '63 Ford Falcon) achieved 22.5 mpg on kerosene at 50 mph. According to the graph, 50 mph corresponds to roughly 20.8% efficiency for the gas engine. This is about 40% higher than the efficiency of the Pritchard engine. Therefore, if the '63 Falcon were powered by a typical gas engine of today, then it would consume about 71% of the fuel energy of the Pritchard car at 50 mph. This corresponds to about 29.5 mpg on gasoline. Note that the Ford Falcon was known to achieve fuel economy in the low 30's (mpg) during actual road tests designed to demonstrate optimal fuel economy (it was a competition with other car models during the 1960's, and the Ford Falcon won with its stock engine). In other words, my analysis here took figures from disparate sources and shows that they agree fairly well. NOTE: Yeah, the stock Falcon did better than 29.5, but it was quite a compact car for its time, and it weighed 2300 lbs vs. the 3200 lb modern car considered in the graph. 

Now, consider an engine (any engine) that can power an automobile and show optimal thermal efficiency in the Normal Operating Range. If an automotive engine can be had to show similar dynamics of peak efficiency in the Normal Operating Range and with little variation in efficiency over a very wide output, yet achieve efficiency in the mid-20's or higher, then it would show superior fuel economy to existing conventional gas cars. An even match requires the efficiency to increase over the Pritchard engine by about 40%. That is, the efficiency has to get the low 20's%. Now, the Doble steam car is known to achieve fuel economy during city driving roughly the same as modern gas SUV's of similar weight (6000 pounds). This was due to the fact that the Doble does not use steam when stopped or while coasting (along with large automotive gas engines showing poor efficiency under lights loads and low engine speeds). This same dynamic would also be favorable for a modernized steam car. That is, fuel economy during city driving could be much higher in a highly efficient modern steam car as compared to conventional gasoline fueled automobiles, and this would take the combined cycle fuel economy higher.



I lifted the following image from the following link: http://www.autospeed.com/cms/article.html?&A=112611 . There is an excellent discussion there of how the efficiency of a conventional gas engine varies over its operating range. A conventional gas engine can show very impressive efficiency. Unfortunately, it has to operate under a limited set of conditions to show this high efficiency. Note the sharp decrease in specific fuel consumption at near 3000 rpm and 25% throttle. This speed is where most passenger cars are geared for highway travel, and 25% load is roughly the output required to maintain highway speeds on level ground. However, the efficiency here is nowhere near peak. This dynamic is the primary reason that hybrid cars show higher fuel economy. A little thought leads to the conclusion that such an engine with a highly variable efficiency profile will never show an average efficiency approaching the peak efficiency value in a real world application where output must be highly variable. This is an important reason why a modern steam engine with a flat efficiency profile is well suited for such applications. Incidentally, it is a major reason why diesel engines see superior fuel economy since the efficiency of a diesel engine is not only high, but it also doesn't vary nearly so much as a conventional gas engine. Also note again that this graph considers traditional (i.e. conventional) gas engines. Modern automotive gas engine systems have been able to improve the efficiency profile significantly with variable cam profiles (like VTEC). One of the most promising systems soon to be used in commercial vehicles is the precise operation of valves using electronically controlled pneumatic actuators. The have been shown to be reliable and to improve fuel economy on the order of 15-20%. The fuel economy of modern and sophisticated automotive gas engine systems are improving significantly. In my opinion, a modern steam car would not be superior with respect to fuel economy to any automobile that uses a fully equipped modern internal combustion engine system that pulls out all the stops. However, I do believe it can be competitive in this respect while being simpler, showing superior performance with high torque and ideal torque profile for the application, and using a much wider range of fuel sources that the IC engine cannot use and with a great deal fewer processing requirements. There will be a time when petroleum reserves are depleted to the point that alternative fuels become economically viable. If the cost of these fuels can be lessened significantly by eliminating the final processing steps (and costs involved in transporting the fuel - in other words, encouraging production of fuels on a regional and local basis) required to make them suitable for modern IC engines, then this will favor a modern steam engine. I believe this dynamic would be necessary to bring a modern steam car into wide use.



See this discussion: http://www.heat2power.net/en__wasteheat_in_ices.php

(*) Both the White and Doble steam power plants have been tested at 14%+ overall thermal efficiency - in particular, a 40 hp White system was tested around 1906 under controlled conditions on a dynamometer at a sustained output of 41 hp and showed just over 14% overall efficiency. The overall efficiency of the Stanley was more typically 6% - a large loss in that system was the boiler, and this was shown by replacing the boiler with a steam generator in one car that improved the fuel range considerably.

NOTE: Here is another account that illustrates well the low efficiency of automotive gas engines under certain conditions. A controlled test was performed at Auburn University to test a truck fueled by a wood gasifier. The truck was a fairly late model vehicle in good running condition, and was capable of normal operation on gasoline. The truck was driven on gasoline at a speed of 50-55 mph on level ground and its fuel consumption was measured (it showed 21 mpg during the test). The truck was then driven under the same conditions, but fueled by the wood gasifier. The energy density of the wood gas was measured, and the fuel energy required to power the vehicle was determined. It turned out that fueling the truck on gasoline required 37% more energy to travel the same distance as compared to wood gas. Note that the energy in the wood gas itself was measured, and not the energy in the wood. There are thermal losses in the gasifier that amount to roughly 25%. However, it turns out these losses are less than the gains on wood gas. So, under the test conditions at least, the truck was significantly more efficient when fueled by wood vs. gasoline. The results are very telling indeed because I know that a gas engine of that design when fueled by wood (wood, not wood gas) shows a net thermal efficiency of about 17-18%. This implies the efficiency of the truck engine fueled by gasoline under these conditions is somewhat less than 17% (just about where the lower end of the "normal operating range" indicates on the graph above - the graph shows 10% of engine rated power at that point - this would be about 20hp for a 200 hp rated engine, and this is roughly correct here: a truck like this has an engine rated at around 200 hp, but requires only about 20 hp to maintain 50-55 mph on level ground). I consider this fascinating because I have had conversations with engineers who not only claim that an automotive gas engine is a lot more efficient under those conditions, and who would predict an efficiency on wood gas roughly half of the measured value, but even denied outright the test results. SUMMARY: The truck, and by implication many conventional gasoline fueled vehicles on the road today, show surprisingly low efficiency during real world driving. The only time the efficiency gets impressive for most vehicles is during highway driving when the engine is operating at a fairly high output relative to its rated power. Even in these cases the average thermal efficiency of the engine is in the low to mid 20's% (diesel engines are much better under just about all conditions by the way).

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## osan

Not exactly steam...

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## buenijo

Hi Osan. That's a very elegant design. Funny, I was reading a description recently about a compounded gasoline internal combustion engine that was manufactured for a short time during the early 20th century. I like how this design shares a low pressure cylinder with two primary cylinders. 

From what I've seen, I expect the peak overall efficiency of automotive internal combustion engines to see the high 30s% in the next 10 years. There are Diesel engines, direct injection gasoline engines, the Scuderi system, and this configuration will also do it. There remains the problem of the relatively low efficiency at low part loads and idling losses, but Diesel and DI lessen this. There is also hybrid systems - but then there is the complexity issue. Actually, if MPG is what's wanted, then the low hanging fruit can be had with smaller cars and aerodynamic designs (like the Elio). I hope the Elio makes it to market. I would buy one.  

Personally, I don't see a practical way for steam power to ever make a serious comeback in the automotive arena - at least not any time soon. However, I think there is a place for small stationary cogen systems fueled by biomass or waste products, and compact solar thermal engines.

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## osan

> Very nice hobby steam engine set up: http://www.youtube.com/watch?v=8FXeYKvQQ6o
> 
> Scale this up about 10 fold and fuel with wood, then it might be useful rather than just pretty! Seriously though, I am impressed. It's a good piece of work. Also, this is large by model steam standards. The engine is rated for 1/4 hp.
> 
> The guy has an awesome web site!: http://rcdon.com/index.html
> 
> Steam project details: http://rcdon.com/html/6ci_steam_engine_project.html
> 
> NOTE: I contacted this individual for some clarification on his system. He is using Teflon compression packing to seal the piston. This along with graphite based packing products is what I'll be trying for my future project. He says it seals very well. He reports that he has only 25 hours on the engine so far, but it still runs as new. He speculates that he will get well over 1000 hours on the seals. Note that Teflon packing generally has a temperature rating of about 500F. The temperature of 100 psi saturated steam is about 330F. However, also note that the piston seal is in contact with the cylinder wall that will be maintained at a temperature roughly equal to the mean between steam generator temp and condenser temps. So, this suggests that Teflon can be used with steam at much higher temperatures. Also, I believe he is using Teflon also to seal the piston valves. This would put a hard limit on the steam temps as the valve sees peak steam temperature. However, poppet valves and bash valves require no such seals.  
> ...


Beware that teflon cold flows.  It is not good as a seal or bearing for some applications.

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## Dr.3D

> Beware that teflon cold flows.  It is not good as a seal or bearing for some applications.


I remember a fellow who used it to seal the screw drive shaft on his boat.   It worked for awhile and then ate into the shaft to the point where the shaft broke off.

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## buenijo

I came across the following description of a small scale steam engine used to power a small boat: www.steamboat.com.au/SL%20ALBA.doc . Of particular interest is the use of a surprisingly small and simple monotube steam generator. The control system for the steam generator is also interesting, and virtually identical in principle to some of the configurations I have considered. I'll provide a summary of the system here.

The engine/expander is a simple single cylinder, double acting, slide valve unit with 1.5" bore and 2" stroke. The steam chest pressure is described at 150-200 psi with engine speeds of 350-400 rpm. This corresponds to a conservative 1/2-2/3 hp at the shaft. The system was clearly not built with efficiency in mind. I expect the overall efficiency of the steam generator alone to be on the order of 50%. Net thermal efficiency is probably 3% at best. The builder noted elsewhere that he gave no priority to efficiency or cosmetics. Note the steam generator. It is made of a length of stainless steel tubing 5-6" mm (1/4") diameter and 40 feet in length. This generates superheated steam at 550-600F. It is a single continuous length of tubing with one end connected to the water feed pump discharge, and the other end is connected directly to the engine steam chest. The water feed pump is driven by a small 12 volt electric motor, and this was selected to provide some control. The motor uses a pulse width modulated (PWM) controller with the potentiometer actuated using a bimetallic strip taken from a small electric frying pan. The strip forces the controller potentiometer as the steam temperature approaches 600F, and this increases motor speed to max. Pumping water into the coil at the max rate serves to cool the coil. It would likely increase engine power as well in this particular set up that uses a more or less uncontrolled wood fire. Engine output is controlled by lowering steam chest pressure by venting steam using an manually adjustable steam relief valve. Again, this is not an efficient system (lots of heat wasted!). However, this is really necessary to do a monotube steam generator relatively simply under these conditions. 

Now, if the system were designed for a constant output, then things could be a lot simpler and more efficient. A small gasification wood furnace can be tightly controlled with respect to output by using a blower fan to control the rate of air supplied. One thing this project shows well is how small a steam generator can be for a useful steam engine. In fact, this 40 foot length of 1/4" steel tubing is large enough to support well over one hp with a more efficient expander, and thermal losses from the steam generator could be low as well with a better coil shape and good insulation.  Steam temperature could be controlled by using a bimetallic strip to control the output of a small blower fan, and this would allow for controlling engine output without compromising engine efficiency (i.e. venting steam). It it also possible to use an RTD temperature probe or thermocouple with arduino to control the fan. I suggest placing a water relief valve at the feed pump discharge set high enough to ensure the steam pressure to the engine is just high enough to support the highest desired pressure. The steam pressure to the engine steam chest could then be controlled using a simple steam throttle. Alternatively, the pressure (and resulting engine power) might be adjusted with an adjustable water relief on the feed pump discharge. This would be acceptable if the system is designed to operate for long periods at a constant rate (which I consider ideal for a micro scale CHP system fueled by biomass).

I disagree on his insisting that the steam generator tubing must be welded or flared fittings. I think a good compression fitting will work fine. I am aware of Swagelok fittings being using with very high pressure superheated steam.

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## buenijo

https://www.youtube.com/watch?v=QJAY6mkxTIg
https://www.youtube.com/watch?v=h_wKu8klZDA

Very clever steamboat. A condenser would make for a dead quiet ride with such a low speed steam engine.

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## buenijo

Jay Leno's new Doble steam car (formerly owned by Howard Hughes):

http://www.youtube.com/watch?v=rUg_ukBwsyo

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## Natural Citizen

> I am wondering why we're not hearing more about this and someone, somewhere, in the process of designing practical graphene batteries for manufacture.


Here is an interesting application...

*Fuel from thin air? Graphene breakthrough may lead to green car revolution*...




> Scientists believe they can use the same material found in pencil lead to revolutionize the green car industry. They discovered that graphene may serve as a fuel cell membrane and even allow the harvesting of hydrogen from air.
> 
> _“We are very excited about this result because it opens a  whole new area of promising applications for graphene in clean  energy harvesting and hydrogen-based technologies,”_ said  Marcelo Lozada-Hidalgo, co-researcher on the study.
> 
> One-atom-thick graphene is the world’s thinnest, but also  strongest, material – 200 times tougher than steel. It is also  the world’s best conductor of electricity. Knowing that graphene  is impermeable to even the smallest of atoms, hydrogen, Geim's  team decided to test whether protons, or hydrogen atoms stripped  of their electrons, were also repelled. 
> 
> _“There have been three or four scientific papers before about  the theoretical predictions for how easy or how hard it would be  for a proton to go through graphene and these calculations give  numbers that take billions and billions of years for a proton to  go through this same membrane,”_ Professor Geim said, who won  the Nobel Prize for Physics in 2010 for discovering graphene  along with his colleague Konstantin Novoselov in 2004.
> 
> The team found that if the temperature was raised and if the  graphene films were covered with a catalyst such as platinum,  then the protons would have little problem in passing  through._“It’s just so dense an electronic field it just  doesn’t let anything through. But it’s a question of numbers, no  more than that. This makes a difference between billions of years  and a reasonable time for permeation. There is no magic,”_ he  added.


Fuel from thin air? Graphene breakthrough may lead to green car revolution

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## Anti Federalist

///

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## buenijo

Just dropping in to link an interesting paper. Note that I don't do research into this topic any longer despite my continued interest. Basically, I've done more than enough research to have a chance at building something useful. Unfortunately, the problem is I do not currently have the resources to make a decent go at it. I simply cannot justify it financially. Maybe some day. Until then I'll share what I may come across and answer questions if anyone cares to inquire.

http://steamautomobile.com/ForuM/fil...N4200_2010.pdf

Fairly recent engineering thesis covering the steam engine designed and operated at the White Cliffs solar thermal plant in eastern Australia. For those who desire to see the original report on this system, see the following link: http://www.rossen.ch/solar/sustain_r...ect_report.pdf 

The thesis spends a lot of time on the steam inlet valve design. Unfortunately, there was a lot of data not recovered from the original work done during the early 1980's. Apparently, despite the work having been done by a university, there was a corporate entity created to oversee the project and much data was subsequently deemed proprietary (and finally lost it seems - I'm guessing someone figured they couldn't make any money off of it, and then just sat on it - what an ass). It's clear from the discussion here (and elsewhere) that the lift pins on the bash valve design see the most abuse and subsequent wear. It seems to be the main problem with the concept. However, according to the initial report the valve lasted well beyond 1000 hours of actual operation - and at an engine speed of 1500 rpm (see page 132 of report). Note that, in my opinion, the bash valve concept is not the best for larger engines as casually mentioned in the report. The recent work of Terrajoule shows that superior results are had from a more traditional steam engine design. However, I remain convinced that this is the best approach to be pursued for those who desire to devise a simple (but useful - as opposed to the toys seen on YouTube and elsewhere) micro scale CHP steam engine system fueled by biomass. The thesis emphasized something that I've held since I considered the problem of a simple micro scale steam engine system. If a bash valve is used, then emphasis should be placed on selecting a durable lift pin that is also both inexpensive and easily replaced. Basically, it should be sacrificial item. Most descriptions I've seen on bash valves report few problems with the actual valve element and seat. The one point of emphasis is to ensure the valve element (often a ball bearing) is harder than the seat otherwise the ball will be worn by the seat and sealing will be compromised. I still like the use of a ball for its simplicity even though other bash valve designs are objectively superior. A hard ceramic ball bearing is the best candidate I've considered (readily available from McMaster). Personally, I tend to believe a small engine operated at relatively low speeds will do well with this basic design.

NOTE: In sections 2.6 and 2.6.1 (and 3.4) of the thesis paper there are interesting observations that suggest a rather ridiculous possibility. (1) It seems the engine had been operated rarely over the previous many years. Yet, there was significant deformation of the lift pins observed. (2) There was difficulty finding specs on the original length of the lift pins. Yet, a set of pins were discovered. Upon measuring, it was found these pins were too long. So long in fact that they prevented the engine from turning over as they forced the balls up against the top of the valve guide plate. (3) Upon measurement of the installed lift pins (that were significantly deformed at their ends) it was found they they would cause similar intereference as described in (2) if they were any longer. This suggests that at one point pins of excessive length may have been installed in the engine and forcefully turned over (likely by starter motor) which crushed their ends. If so, then the existing deformation pattern was not caused by normal operation. It seems an interesting possibility that was considered on page 35 with the parting comment "However, if this scenario was the case then there is the chance that the material used to construct the pins is appropriate and can with stand the stresses; in which case this investigation may all have been in vain and someone has a lot of explaining to do." Hilarious! Well, at least get got his degree. 

http://www.steamautomobile.com/archivepdf/SAv27n2.pdf (see page 32) One of original advisors on the White Cliffs steam engine design chimes in on the documented reliability of the engine system. At the time his writing this comment (1986) the engine valve system had documented 3000 hours of operation at 1500 rpm. I'd say this proved the concept as viable. The writer also notes that a lower speed engine will last much longer, all else equal, due to the lower forces on the valve system. In other words, I think there is good evidence to show that the basic bump valve approach is not flawed, and can therefore be used to devise a reliable engine system that also shows high efficiency. Since the basic approach is the simplest possible way to design a steam expander, then it seems the obvious choice to simplify the overall project.

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## buenijo

http://www.kimmelsteam.com/docs/Econ...n-Woodruff.pdf

An excellent discussion on the efficiency of steam engines - one I should have posted earlier. Good read for anyone genuinely interested in the topic.

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## buenijo

Great resource on steam engine system education:

https://steamautomobile.com/wsa/tutorial/index_2.htm

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## buenijo

https://www.youtube.com/watch?v=-85qglTdsE4

This is one of the better micro steam engine projects I've seen on YouTube (most of them are worse than useless). While this engine is little more than a toy since it's not configured to do anything useful, it does show promise as it's based on proven principles. Note a separate steam cylinder is mounted on the lower stock gas engine piston via a straight piston rod sealed at the base of the steam cylinder (been done many times before). The gas engine piston is used as a crosshead here. I expect the compression rings on the lower piston were removed to lessen friction. In my opinion, this approach is the best for many reasons and is how I would personally pursue a serious project. Unfortunately, there is no load on the engine, but it seems responsive for such a small cylinder and modest steam pressure (200 psi - while this may seem high, this engine a lot of compression that reduces steam admission). This is a "bump" valve uniflow using a check valve taken out of a cat water pump to admit steam. While this particular approach to fashioning a steam valve is clever, it would not likely stand up to abuse - but it's a good video to provide a glimpse into the approach. Note the absence of any steam chest. Rather, steam goes straight to the valve through a 1/4" line via a small ball valve. Other bump valve conversions I have seen take a 1/4" line directly to a fitting that contains the bump valve with practically no steam volume maintained above the inlet valve. With sufficiently high pressure steam this can be done (of course, a steam chest would be beneficial for higher engine speeds if desired). This basic configuration can show high efficiency and high power with the right design. Right at 15% overall efficiency is not unreasonable with sufficiently high steam pressure and temperature, and sufficiently high expansion and condenser vacuum on exhaust (actually, 20% could be achieved, but that would push the limits). That's another point - this engine exhausts to atmosphere, but it would be a lot more powerful with a vacuum condenser. With much higher steam pressures it would be a beast. Note that the peak cylinder pressure in a small gas engine is well over 500 psi. So, a smaller steam cylinder could use steam at even higher pressures without unduly stressing the crank in such a system. Impressive power is possible if one desires it. Of course, a furnace and steam generator is required - along with condenser and feed pump.

https://www.youtube.com/watch?v=cU4gM0jUDbk This is why you use a separate steam cylinder. Steam gets into the crankcase and mixes with the oil. Best not to deal with it. However, oil free of detergents (to prevent emulsification) can and has been used where the oil/water in the crankcase and the water/oil in the condensate move to a centrifugal separator. In that case the two are separated and the oil and water are reused. Sort of a pain for a micro system, and the reason I think experimenting with oil free systems is the best way to go. However, the process is proven to work well with steam temperatures up to 1050F in a single acting uniflow engine. The main difference there compared to traditional steam engines is the oil was not injected into the steam line. This was done in older steam engine designs to lubricate the inlet valve (generally slide or piston valves). Poppet valves and bash/bump valves do not require lubrication. Therefore, oil can be injected into the cylinder where average temperatures are much lower than peak temperatures. For example, in the Carter engine that used steam up to 1050F, the oil was injected directly onto the piston rings when the piston reached the end of stroke, and the rings were accessed from the uniflow exhaust ports in the cylinder wall. The rings were "bathed in oil" by the Carters' description using about one quart of oil every ten minutes of operation. All oil was recovered in the separator and reused. Oil lubrication has been shown to work in this kind of system where the average cylinder temperature is less than 650F. The Carter system had an average temperature of about 625F (the mean between the peak steam temperature of 1050F and the condenser temperature which was about 200F).

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## buenijo

Recreation of 1920's steam powered machine shop (actually in operation and generating revenue). Series of 10 videos on channel so far. Excellent information:

https://www.youtube.com/channel/UCBd...nGoJUag/videos

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## buenijo

I mentioned the start up company Terrajoule in post #175. I came across some recent information on their work. See the following video: https://www.youtube.com/watch?v=bHlAohwtLcs . The audio quality of the video leaves a lot to be desired, but the discussion is very interesting. As a recap, know that Terrajoule is using reciprocating piston steam engines in a solar thermal stationary power generation system with very inexpensive energy storage that permits 24/7 operation up to full rated power. The prototype plant they have in operation is using an insulated steel pressure vessel (a large propane storage tank) filled with water as their energy storage vessel. However, the next system is to make use of steel piping with SOIL taken from the site used as the primary thermal mass. The purpose is two fold: (1) to achieve somewhat higher temperatures in their storage (since piping has higher pressure ratings than a large tank), and (2) to store additional energy using soil (an even more cost effective means for energy storage). As before, the piping will be filled with saturated water under pressure. BTW, the use of piping permits somewhat higher pressures and temperatures, and also increases the surface area/volume ratio to allow for effective heat exchange with the surrounding soil (note that the thermal mass is contained ABOVE GROUND - it is NOT buried - rather, soil is taken from the site as a very cost effective thermal mass and used to store most of the heat). The general trend of the discussion is that the physics and economics of solar thermal power generation with thermal storage makes it cost effective at relatively small scale. It turns out there are many dis-economies of scale for these systems. This conclusion implies a return to steam engine technology that is far more efficient at the smaller scales. Also, the argument is for decentralized solar thermal since steam engines are excellent for meeting highly variable power demands and without suffering a loss in efficiency, and there are also opportunities for cogeneration in these settings. In short, solar thermal + steam engine at small to medium scale solves the problems better than alternatives. Note the smallest size of Terrajoule's modular system is 50 KW peak output with 20 KW average (continuous) output. 3S Power is currently looking to power rural towns and farms in regions that see a combination of high solar insolation and high electricity prices with the two best candidate regions being Australia and Chile.

* There is a particularly interesting discussion of the efficiency of steam engines vs. steam turbines as a function of scale, or power output starting at 10:40.

Also mentioned during the video is a start up company based in Seattle that is working on converting existing diesel engines to steam engines. The company web site is here: www.practicalsteam.com. Unfortunately for applications considered in this thread, they are targeting medium scale systems with power levels similar to those targeted by Terrajoule (i.e. no micro scale systems suitable for a household). Still, I like the trend - it seems the benefits of steam engine systems are starting to become recognized.

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## buenijo

www.lightsail.com

Interesting start up company. They are looking to store energy using compressed air. They have a system that increases significantly the efficiency in compressing air - and subsequently expanding the air to retrieve the energy. Interestingly, this idea is NOT new. In fact, I considered it independently as a means to capture heat of compression that is normally lost. It's very simple. When air is compressed, then the mechanical energy used to compress the air is transferred to the air molecules. This results in a rise in temperature. Well, the increase in temperature also increases the pressure (all else equal). So, one ends up having to use more work to compress the air when this heat of compression is not efficiently removed. The solution here is to use a fine water spray to moderate this rise in temperature. The water is heated in the process, and the hot water is separated and stored. When the air is expanded, then the hot water is again sprayed into the air stream. Well, expanding the air cools it, and the water spray heats it up. So, it works to increase the volume of air by increasing it's temperature - meaning, more work can be derived from the expanding air through this process. Basically, it significantly increases the efficiency of the process. Overall efficiency demonstrated is about 70% of the electricity used to power the motors that drive the compressors is recovered from the generators driven by the expanders. Much of the loss is in the motor and generator, so it can't get much better. Alternatively, the system could use the heat of compression for useful applications (like water heating in buildings or space heating), and when the heat is used in such applications, then the expanding air might be used in other ways such as air conditioning - configurations I have discussed elsewhere. The system as I understand it uses piston compressors that operate also as expanders. In many ways, the system is similar to the Terrajoule system. However, compressed air requires much higher pressures to achieve useful energy storage capacity. They are talking about carbon fiber tanks for very high pressure. Well, that's a problem for me. Personally, I am more impressed with the Terrajoule system. Still, this is interesting. What I like about Terrajoule is the elegant simplicity. By contrast, this system seems more complicated and costly.

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## buenijo

I just became aware of a small scale steam engine system constructed and operated during the early 1980's. It was used to heat and power a modern home in Pennsylvania. It was fueled by anthracite coal. I understand there is an ASME paper describing the details. So, if I can get the paper, then I will post it here.

The details I acquired show the system was extremely efficient. Well, actually, since it used saturated steam at only 135 psig and atmospheric exhaust, the highest possible efficiency is very low under these parameters. However, it showed 80%+ of Rankine cycle efficiency (or theoretical maximum). I would not have thought it possible to do so well in so small an engine (actually, until I get the ASME paper, then I am going to doubt the figure). The White Cliffs expander was measured at about 70% of Rankine cycle efficiency using saturated steam at 540 psig and exhausting to a condenser at 160F (roughly 3.5 psia). There were additional losses in that engine due to the incomplete expansion (since it used high pressure steam plus a condenser under vacuum), clearance volume losses due to the bump valve configuration, thermal losses mainly from the high temperature differential in the cylinder (but also the higher steam temperatures), and the higher pressure likely contributed to steam leakage past the rings. Also important is small steam engines are very poor at extracting work from low pressure steam. So, a small engine with atmospheric exhaust can potentially show a very high percentage of theoretical maximum efficiency provided the other losses are minimized.  

The expander was a single cylinder, single-acting, uniflow piston engine converted from a small industrial internal combustion engine. The steam admission used a single poppet valve with a push rod and cam. The system operated 24/7 during the heating seasons over a period of four years. Typical operating speed was 600 rpm. Power output was about 2 hp.

http://www.thesteamboatingforum.net/...ile.php?id=187
http://www.thesteamboatingforum.net/...ile.php?id=186

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## buenijo

Still doing a bit of casual reading on steam engine systems. The same engineer who devised the residential scale CHP steam engine system described in the previous post also devised and operated a small steam generator using a simple principle I considered years ago. Apparently, it works very well. A problem with traditional monotube steam generators is the water feed rate must be closely matched to the furnace output. Otherwise, insufficient water flow can lead to excessive temperatures and possible tube burnout (or lube oil destruction), or excess water flow can flood the coil and carry water into the engine. The solution here is simple: just pump excess water at all times, then use a small separator vessel to accept the steam/water mixture from the tube - pressurized saturated steam is taken from the top and saturated water is drained from the bottom. The water level remains more or less constant as long as the orifice to the drain line is properly selected with respect to size. Turns out the mass flow rate of water through an orifice is on the order of 10 times greater than steam. So, very little steam can escape. As long as what little steam escapes has its heat captured and regenerated into the system (along with saturated water that drains through), then there is no loss beyond the very slight mechanical energy needed to operate the pump at the higher rate. Well, this reminded me of another idea. As long as the peak temperature of the water/steam is limited, then oil can be circulated with the steam/water without separation. This has been done before. As I recall, the early Doble steam cars did this for a while. However, they did show some problems that I suspect were caused by excessive steam temperatures. Taking the temperature down a notch while using very good synthetic oil should solve the problem (I speculate). Maintaining a steam generator of the type described here would allow for never superheating the steam - so the oil would be positively protected from excessive temperatures. Yeah, efficiency would be capped, but dry saturated steam can show good results - especially at higher pressures. NOTE: However, the steam/water separator should do well to remove most of any lube oil. Therefore, the saturated steam taken off the top could be shunted through a superheater to increase efficiency.

An interesting dynamic on heat transfer is counterintuitive to many. Consider the following: compare two steam generator tubes (one steel and one copper) that have the same dimensions. Now, with all else equal, which one will generate steam at the higher rate when heated by the same furnace? The answer is the rate will not differ by much. The higher thermal conductivity of copper is not a significant factor here because it's the low rate of heat transfer from the flue gases to the outer tubing wall that is the bottleneck. It turns out the temperature of the inside tube wall is on the order of only 10F higher than the steam/water flowing within. The outside tube wall temperature for the copper might be just 2-3 degrees F hotter than the inner wall temperature. The outside tube wall temperature for the steel will be higher than the copper, but only on the order of 20-30 degrees F (based on the thermal conductivity of copper being roughly 10 times higher than carbon steel). So, this lower outer tube temperature for copper makes negligible difference to heat transfer rates when the furnace temperature is 1500F. Now, if one were using a liquid heat transfer fluid to generate steam, or using much lower temperatures, then copper might make sense - but not when using a furnace directly. Anyway, considering this, then it seems reasonable to circulate oil with the water/steam provided the steam generator tubing is always flooded with some water thereby making superheating impossible. If the pressure is set at say 300 psig, then the temperature of the oil could never rise above the saturation temperature for water at this pressure (which is 421F). Many synthetic lube oils can handle this temperature. Yeah, the efficiency of the system would be limited, but I've shown that it's possible to achieve 10-12% overall thermal efficiency at this steam temperature - with a good design. If the heat from the system is the main energy requirement, then efficiency doesn't matter so much. However, again, optimizing efficiency is important because good design can increase the efficiency many fold over poor design - and while being simpler mechanically! For example, the steam engine system that started this thread is quite literally 2-3% efficient in converting the chemical energy in wood to shaft work. A safer, simpler, and much more compact system can increase efficiency four fold - and it can be practical in the sense that it need be fueled only once or twice daily while it runs unattended to provide heat and electricity. The most recently described steam system proves it's possible to do this - after all, it was constructed and operated over a period of four years to heat and power a modern home.

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## buenijo



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## youngbuck

> 


  I would like to buy one, or a build one. Doesn't appear that it's available in the US.

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## Anti Federalist

Just found a lead on a 7 HP vertical single, like the one in the OP, in working condition for a decent price.

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## sparebulb

> Just found a lead on a 7 HP vertical single, like the one in the OP, in working condition for a decent price.


This thread is too long to review, so are you talking about a Lister engine?

And if is, is it Limey or Injun built?

Edit:

Oh, hell.

I just reviewed the OP.

Nevermind.

Steam, huh?

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## Anti Federalist

> This thread is too long to review, so are you talking about a Lister engine?
> 
> And if is, is it Limey or Injun built?
> 
> Edit:
> 
> Oh, hell.
> 
> I just reviewed the OP.
> ...


The Limey Listers are going for a small fortune these days, since they have been banned for import by EPA fatwa

Yup, steam...or the old "make and break engines", those have potential as well.

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## osan

Dan Gelbart is a rather interesting fellow.  Here is something he threw together in his free time:

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## Anti Federalist

> The Limey Listers are going for a small fortune these days, since they have been banned for import by EPA fatwa
> 
> Yup, steam...or the old "make and break engines", those have potential as well.


You can get the Injun ones, but they require some post purchase fiddling, since to get around the EPA _fatwas_, they have to be imported as "air compressors" and then the fule system added after the fact.

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## Anti Federalist

> Dan Gelbart is a rather interesting fellow.  Here is something he threw together in his free time:


Electronic timing on single stage steam engine...fascinating.

Was this *his* invention?

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## osan

> The Limey Listers are going for a small fortune these days, since they have been banned for import by EPA fatwa
> 
> Yup, steam...or the old "make and break engines", those have potential as well.


You can get single- and double-lung hit-or-miss engines that are made right here in the USA._  Arrow Engines_ is a primary source.  We were to be the sole representatives for sales and service for the states of WV and PA.  Gary, my "partner" was one of those perpetually struggling losers who, as it turned out, was more afraid of success than he was covetous of it.  Just as I was getting the relationship established with Arrow, that $#@! tells me that things were happening "too fast" and he pulled out, retired, and moved to Florida.  $#@!.  What pissed me off most was that he asked ME to run the business for him.  All that jerkoff had to do was sit back and count money, and it likely would have been substantial amounts.  I SO dislike stupid, timid, do-nothing people who shy away from success because it asks of them just a smidge of committed effort.

My indigestion aside, Arrow makes engines that can run for years, virtually non-stop, and are extremely fuel-efficient.

You're welcome.

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## osan

> Electronic timing on single stage steam engine...fascinating.
> 
> Was this *his* invention?


I suspect so.

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## Anti Federalist

Just seeing this now...nifty, thanks.

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## buenijo

The following is a video of one of Tiny Tech India's steam engines. It describes a very clever mechanical "Buckeye" speed governor system. It is difficult to understand the description. The basic idea is the combination of spring tension and the force on the flyweights act to rotate the eccentric to adjust the steam valve cutoff as rpm changes. This is more efficient than using a governor to position a steam throttle valve. Very clever indeed. See description of operation here: https://www.loc.gov/resource/rbpe.13803100/?st=text







Video showing complete assembly of one of their engines. Interesting to see the eccentric includes ball bearings. I am not sure why they installed the compression rings on the crosshead piston(?) - to lessen crankcase oil from escaping perhaps? It seems desirable to remove these to lessen friction. I can't help but wonder if the compression rings were placed as a matter of habit. 




I now believe a good CHP steam engine system could be had using one of their compounded engines. It could show reasonably high efficiency, and the ability to drive a generator head directly using one of their governors is a big plus. The improvements Mr. Desai has made to his engines over the years include: (1) installing steam cylinder onto small stationary diesel engine crankcases using the lower trunk piston as a crosshead guide for the steam piston, (2) using gun metal steam cylinder liner, (3) replacing slide valves with piston valves, (4) providing the Buckeye speed governor. The manual cylinder lubrication pump is undesirable and should be replaced with a displacement lubricator or mechanically driven oil pressure pump.

ADDENDUM: I corresponded with Mr. Desai during May of 2020. Unfortunately, despite the incremental improvements he made to his steam engine system, they have remained a net loss for his business. Therefore, he will no longer be manufacturing steam engine systems. I suggested he make contact with Village Industrial Power (see later post #226) to see about becoming a distributor for their more modern steam engine system. I admire Mr. Desai's dedication and vision. There is potential for small scale, biomass fueled, CHP steam engine systems. Unfortunately, his systems are based on primitive designs that died for very good reasons.

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## buenijo

A simple and crude, but fairly high output wood fired monotube steam generator. While not efficient, it shows that a surprisingly simple system can generate steam at a high rate. This unit produced steam at a rate of 3 kg per minute. For reference, Mr. Desai's 6 hp compound steam engine consumes 1 kg of steam per minute at full power.

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## buenijo

GOOD ARTICLE: https://medium.com/impact-engineered...e-dce965b13dc9

ADDITIONAL INFORMATION: https://poweringag.org/innovators/bu...ower-provision

WEB SITE: https://www.villageindustrialpower.com/

Highlights:
1. Biomass fueled including many readily available crop residues unsuitable for a biomass gasification engine system.
2. CHP 
3. To be mass produced in India 
4. No oil lubrication!
5. Double acting uniflow with high recompression
6. Impulse steam admission valve - no valve gear 
7. Appears to be mechanically very simple ("the unit can be taken apart and put together in an hour with two wrenches")

*EFFICIENCY:* The system is described as generating AC electricity at a NET efficiency ("fuel to electricity") of 10% at 300C steam (572F) and atmospheric exhaust. Peak steam temperature is described in the patent as 700F. The steam pressure is described as 300-400 psig. These figures correspond to a steam cycle efficiency approximately 50% of Carnot efficiency which is just about as good as it gets at this scale. The boiler is described as "70% efficient". More important to real world operating efficiency is a uniflow of this basic design is known to show a flat efficiency profile. This is in stark contrast to gas engines. I expect the efficiency at 25% rated load to be close to the full load efficiency - and everywhere in between. Whereas, the efficiency of a gas engine generator at 25% rated load is often about half the efficiency at rated load. That noted, I consider the wide fuel capacity of the system, its mechanical simplicity, and the ease in heat recovery as the more important qualities. For example, the sophisticated Power Pallet by All Power Labs lists (1) wood chips, and (2) nut shells (walnut and Hazelnut) as the ONLY approved fuels for their unit. Of course, the wood chips must processed to the proper size and screened of fines, etc. 

CONS:
1. Large pressure vessel boiler with only 70% efficiency. It appears that the system requires an operator. In my opinion, the use of a large pressure vessel boiler renders the system unsuitable for residential combined heat and power (except perhaps community scale). However, it seems a good fit for micro scale industrial CHP in "third world" settings.
2. Seems loud and with much water loss. However, this can be relatively easily resolved.
3. Much vibration. However, this also may be a function of limited development.

I am surprised this flew under my radar. Interestingly, shortly after the turn of the century, the inventor spent several years directing a team to develop a biomass gasification engine system for the same applications. However, the complications associated with that technology led him to steam power. See the article I linked. The benefits of this kind of system as discussed by the inventor are spot on.

PATENT: https://patents.google.com/patent/US9657568 Brilliant design similar in principle to previous approaches. The steam inlet valves are opened by steam recompression. There is no lift pin. The cut off is partly controlled by engine speed in a negative feedback that causes less steam to be admitted when engine speed increases, and vice versa. However, a cam limits the valve opening to control the cutoff more precisely. Note the valve is a curved spring that covers steam admission ports in the cylinder head. A very similar design was done in a steam engine I described in a previous post on this thread.

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## Anti Federalist



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## tod evans



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## Badnon Wissenshaftler

*A Genuine 1870 Solar-Powered Steam Engine*

              Reprint of 1870 article about a solar-powered steam engine that  appeared in The Technologist magazine, which proves that alternative  energy is nothing new and that its benefits have long been known.

https://www.motherearthnews.com/gree...e-zmaz75ndzgoe

I  don't know if this has been mentioned in this thread, as it's  ridiculously long and I'm quite late to the party, but I think it's  worth note.

This, combined with the wood-fired option, could've stopped "the grid", or centralized power generation, before it was ever born, at least in many areas.  We'd be a better country for it.

That said, solar panels are quite inexpensive these days if you shop around.  I just bought 4 kW worth for <$600.

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## Anti Federalist

Neat, I can't recall ever hearing a tractor "stack talk" like that.




>

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## Anti Federalist

171 hp and *5000* ft/lb of torque.

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## tod evans



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## tod evans



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