Hmmm. I actually find the following explanation a pretty good
description of the principle, if we assume the reader knows the
Stirling cycle. I cannot comment on the suitability of CO2 in the
secondary circuit, but it seems clear that the primary circuit is a
Sirling engine with helium as a working medium, and that the CO2 is
used to transport heat from the refigerated area to the Stirling
engine.

http://www.avxcel.com/free_piston_stirling_cooler.html
http://www.avxcel.com/heat_rejection.html
http://www.avxcel.com/marine_refrigeration.html


"RJK" == Richard J Kinch writes:

RJK Ole-Hjalmar Kristensen writes:

If you look closer at the technology you will find that the working
fluid is helium.

RJK That's rather obscurely and incompletely explained on the Web site, being
RJK that purveyors of perpetual motion cannot, of necessity, be too specific
RJK about how it is achieved.

RJK But if you're correct about the helium and Stirling, then so much the more
RJK is this made not credible.
RJK --

C++: The power, elegance and simplicity of a hand grenade.