As is common knowledge, solar energy installations are only as good as the direct sun they face. There’s nothing to do at night, and clouds are a bad thing. In an interesting turn of events, solar energy appears to have overcome that giant hurdle, in what some optimistic people call the “Holy Grail for Renewable Energy.”
A demonstration project by Keahole Solar Power in Hawaii has an installation of Sopogy “Micro-scale Concentrating Solar Power Concentrators” with thermal energy output of 2 megawatts. The main players here are the ElectraTherm “Green Machines” that run on the organic Rankine Cycle and are waste heat generators.
ElectraTherm units can operate at a temperature difference of just 20 degrees, and can vastly improve the efficiency of a system. Output (hot water) from the solar power concentrators can be put to its conventional use, and then handed over to ElectraTherm units which generate more electricity while consuming only a small fraction of the generated Btu.
It is believed that if all waste heat were used to generate power and heat water, these installations could be used through night and without interruption from unfavorable weather.