The UTRC “lower-temperature geothermal power plant” can be thought of as a reverse cooling system.
The new turbine is essentially a refrigerator compressor running backwards
The modular, 200-kilowatt power plant from UTRC can convert temperatures as low as 165°F into electricity. [low enough for solar too] The technology is similar to steam engines, except that steam or hot water vaporizes a hydrofluorocarbon refrigerant that drives the turbine. And the refrigerant has a lower boiling point than water.
via WorldChanging