Pellet generator

[Shark]

Interesting:
http://pelheatblog.com/2009/10/23/wood-pellet-fuel-generator/

[rreidnauer]

Looks to be a radial piston steam engine. I had made drawings to build a smaller one myself years ago.
http://img.photobucket.com/albums/v328/titantornado/Radial_Steam.jpg
I wouldn't call it highly efficient though. I imagine what they feel is efficient is the closed loop water/steam circuit. But that's not efficient at all. Imagine how much heat energy is being dumped through the radiator to condense the water.

The efficiency and operating costs would be pretty easy to calculate. Just find out what the BTU rating for wood pellets is, which can be converted to Kwh quite easily, then subtract a conservative 20% for losses. I doubt the cost of wood pellets would be very cost effective electric. But, if you could feed it some sort of free biomass instead, this generator would have merit.

[rreidnauer]

I reviewed the video again, and I noticed they are using single acting cylinders for their engine. (they only provide power on the push stroke like a 2 stroke engine) My design is actually dual acting, so it would be more like a 10 cylinder engine since it has both a power push and a power pull stroke. Much better use of steam energy, and much more power in a smaller package.

[ChainsawGrandpa]

Saw this link several years ago.
Still think it's interesting. Very
effecient. Maybe it could be
used with a black concrete heat
sink, and the cooling side could be
immersed in a near-by stream.

http://belize1.com/BzLibrary/trust39.html

G'pa

[rreidnauer]

I wasn't familiar with uniflow steam engines, so I did a Wikipedia search. They aren't all that great for efficiency from what I read. I guess that does explain their rather short footnote in history. HOWEVER, I do like the idea of using something other than water for the vapor/fluid circuit. (in this case butane) That seems like you could do a lot more with lower temperature differentials. I thought about using propane for similar projects, but butane is probably way more effective due to it's fairly low liquid pressure.

Ironically, I also have made drawings of several dual acting, linear steam engine pumps when I was looking for a way to make a small boiler injector pump. My designs didn't require any additional timing complications. Versions 2~4 detail the timing.

Version 1
http://img.photobucket.com/albums/v328/titantornado/Version1.jpg

Version 2
http://img.photobucket.com/albums/v328/titantornado/Version2.jpg

Version 3
http://img.photobucket.com/albums/v328/titantornado/Version3.jpg

Version 4
http://img.photobucket.com/albums/v328/titantornado/Version4.jpg