A 3 MWth parabolic trough CSP plant operating with air at up to 650 °C

Parabolic trough concentrating solar power (CSP) has long proven to be among the most viable options for large-scale solar electricity generation. However, conventional solar parabolic trough plants suffer from several technical and economical drawbacks. These include most notably a maximum operating temperature limited to below 450 °C, a difficulty in creating rigid metallic support structures with large trough apertures, and the need for complex thermal energy storage (TES) technologies. This has impelled the development of a novel trough-based CSP system comprising a 9 m aperture parabolic trough concentrator based on inflated metallized polymer films mounted on a concrete support structure, coupled to a solar receiver based on air as heat transfer fluid and to a packed bed of rocks sensible heat storage. The first power plant with this technology, with a nominal thermal power output of 3 MW_th, has been constructed in Ait Baha, Morocco. We report on the details of the system and its components.