Solar thermal power plants work by concentrating sunlight onto a receiver using mirrors or lenses. The receiver absorbs the sunlight and converts it into heat, which is used to generate steam. . Solar thermal energy (STE) is a form of energy and a technology for harnessing solar energy to generate thermal energy for use in industry, and in the residential and commercial sectors. See more pictures of green living. Most of us don't think much about where our electricity comes from, only that it's available and plentiful. As of the end of 2024, global renewable power capacity reached 4,448 GW, with solar accounting for 1,865 GW.