A parabolic trough is a type of solar thermal system that utilizes large reflective parabolic troughs to concentrate solar energy onto a central receiver tube, where it is absorbed. The troughs rotate on one axis to track the movement of the Sun throughout the day. A working fluid, typically oil, is circulated through the receiver and heated to temperatures of around 400ºC. The absorbed heat is then used to generate steam, which is used to power a conventional steam turbine generator. Some parabolic trough systems are capable of generating steam directly.
