Is supercritical CO2 The Path to Less-Expensive, “Greener” Energy?
The Machine Design magazine's article:
Much of the world’s electricity comes from turbines powered by steam created by the heat from nuclear reactors, solar collectors, and burning fossil fuels. Most of those turbines and power plants use the Rankine cycle in which pressurized water is boiled into steam and then expanded through a turbine to turn a generator, a roughly 33% efficient process. That means 67% of the heat created is thrown away as waste and not converted into electricity. (For comparison, Thomas Edison’s first steam-powered generator in 1892 was 1.6% efficient.)
To wring more efficiency from the process, engineers in national labs and private industry are developing turbines based on a recompression closed Brayton cycle (RCBC) and using supercritical carbon dioxide (sCO2) as the working fluid.