Hot Air Engine

[OG LIM]

A Stirling Engine, often called a "", uses an external heat source to repeatedly heat and cool a volume of gas. No matter if it is solar energy , cattle gung...+ , the engine can run. The pressure fluctuations caused by the expansion and contraction of the gas, acting on a piston , provide the force necessary to make the engine run.

http://khsolutions.tripod.com/index.html

[elmerfud]

Hot air is in abundant supply from the US whitehouse I do beleive!