I am saddened by the ignorance displayed on these comments. What the man (Harry Schoell - company CEO and inventor or the system is talking about is a steam engine, not a Stirling engine. The term "external combustion" is IMO misleading - less so when applied to a Stirling engine. In fact the steam that drives the engine is generated by a separate boiler ("separate combustion" might be a more appropriate term); the water contained therein being heated by combusting fuel or by heat recuperation. The more sophisticated version uses liquid or gas fuel that swirls inside the red combustion chamber in a cyclone (as the man explains) and produces steam at extremely high pressure and temperature in a supercritical state. This steam turns the radial motor, the exhausted steam playing on rotating plates that condense it back into water. This then goes round again and back into the boiler (or, if you prefer, "steam generator"). It thus works in a closed cycle. Schoell also claims that the system acts as an air scrubber eliminating CO2, although I can't for the life me see how. I posed this question to him a few months ago and hope that one day he will find time to answer my mail.
The waste heat engine employs a more conventional water tube boiler (I suspect that the demonstration engine is driven by compressed air) at much lower pressure. This is far less efficient than the cyclone generator, but is probably the only solution in a hybrid set-up and would certainly improve overall efficiency. It is also more bulky.
I can only wish Harry Schoell the best of luck in his interesting and important venture.
I tend to view "external combustion" as a euphemism" avoiding the use of the word "steam engine" due to inrained prejudice, especially among the older generation. Well, a rose by any other name... Anyone wishing to know more would do well to read through the technical papers on Schoell's site http://www.cyclonepower.com/tech_papers.html
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I am saddened by the ignorance displayed on these comments. What the man (Harry Schoell - company CEO and inventor or the system is talking about is a steam engine, not a Stirling engine. The term "external combustion" is IMO misleading - less so when applied to a Stirling engine. In fact the steam that drives the engine is generated by a separate boiler ("separate combustion" might be a more appropriate term); the water contained therein being heated by combusting fuel or by heat recuperation. The more sophisticated version uses liquid or gas fuel that swirls inside the red combustion chamber in a cyclone (as the man explains) and produces steam at extremely high pressure and temperature in a supercritical state. This steam turns the radial motor, the exhausted steam playing on rotating plates that condense it back into water. This then goes round again and back into the boiler (or, if you prefer, "steam generator"). It thus works in a closed cycle. Schoell also claims that the system acts as an air scrubber eliminating CO2, although I can't for the life me see how. I posed this question to him a few months ago and hope that one day he will find time to answer my mail.
The waste heat engine employs a more conventional water tube boiler (I suspect that the demonstration engine is driven by compressed air) at much lower pressure. This is far less efficient than the cyclone generator, but is probably the only solution in a hybrid set-up and would certainly improve overall efficiency. It is also more bulky.
I can only wish Harry Schoell the best of luck in his interesting and important venture.
I tend to view "external combustion" as a euphemism" avoiding the use of the word "steam engine" due to inrained prejudice, especially among the older generation. Well, a rose by any other name... Anyone wishing to know more would do well to read through the technical papers on Schoell's site http://www.cyclonepower.com/tech_papers.html