How Parabolic Trough Works
Solar fields using trough systems capture the sun's energy using large mirrors shaped like a parabola, or a giant "U," that are connected together in long lines that track the sun's movement throughout the day. When the sun's heat is reflected off the mirror, the curved shape sends most of that reflected heat onto a receiver pipe that is filled with a specialized heat transfer fluid. The thermal energy from the heated fluid generates steam and electricity in a conventional steam turbine. Once the fluid transfers its heat, it is recirculated into the system for reuse. The steam is also cooled, condensed, and reused. Heated fluid in trough systems can also provide heat to thermal storage systems, which can be used to generate electricity at times when the sun is not shining.