I just ripped it off the net. It is just the limiting Carnott efficiency 1-t/T like. Yes there are small Stirlings that can convert down in the sub 100C range fairly efficiently, but with them you would have to go heat>mechanical >electrical> control you cell. Peltiers give you direct heat > electrical but you are lucky to get 5% in the real world on those and that would mean a COP of 20 for a self sustaining thing. You also can get heat mechanical via things like NITINOL wire systems and Minto wheels at fairly low temps. [my target for NI is 2 to 3:1 but not self sustaining, I doubt it will be convincing to outsiders- just a start. I do have one sample though that I might can get self heating enough to do mechanical work with a toy Stirling. But, as usual, not at levels to be free from fraud attacks] Jed- do you know who/what is the demo listed for ICCF Monday evening? D2 Date: Tue, 4 Jun 2013 10:51:00 -0400 Subject: Re: [Vo]:A Couple Hundred Bucks Maybe... From: jedrothw...@gmail.com To: vortex-l@eskimo.com
DJ Cravens <djcrav...@hotmail.com> wrote: must be connected to the mains------bingo- if your process requires electrical input you must have a high COP. Where did that graph come from? Did you make it? I have never heard of mechanical work from temperatures below 100 deg C. By the way, I wrote: "These [low temperature] devices would reduce electric power consumption by a large margin, and eliminate the use of natural gas for everything but cooking." I meant in household (domestic) applications. These would have to be driven with mains electricity. Or perhaps with a Hot Cat power generator. Energy applications are often divided into domestic, commercial, industrial and transportation sectors. - Jed