The missing link in residential scale solar and other heat generated electricity has been a practical low temperature, low pressure steam engine. Now 230 - 300 degF heat can create realistic amounts of electricity.
High Latitude Solar in Maine has developed a concentrating parabolic trough collector in panel form to compete head on with evacuated tube collectors in price and performance. We then wanted to use it to generate steam to drive a steam engine-generator. Experimenting with conventional steam engines showed how extremely inefficient they are with low temperature 50 - 100 psi steam. We have solved this problem and it is now available for purchase for use with our solar collector, any evacuated tube collectors, or even with just a tube coil in your woodstove or oil furnace.