--Aha! Looks to me like a variation on the venerable Stirling
engine. That means not a lot of torque, but a sealed system; i.e. all you
need is an adequate delta-T between hot end and cold end. For Stirlings this
number can be as low as, IIRC, 70degF . If you can narrow the delta-T
further you might have something.
"Steamboat Ed" Haas : The impeachment process
Hacking the Trailing Edge! : exists for a reason...
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