Parabolic Mirrors for a 100 m-long Parabolic Trough in Beijing Badaling Solar Power Test Plant

From 2009 to 2010, in order to construct a 100m-long parabolic trough in Beijing Badaling solar power test plant, the parabolic mirrors (PMs) were developed by using the car windshield manufacturing technology. The PM in this design consists of a 1.1mm-thick mirror with a back-surface silver coating attached to a glass backing plate preformed to a parabolic shape. The PMs in this design adopted similar automobile windshield manufacturing process. The contours of the PMs were detected using a 3 dimensional coordinate measuring machine (3DCMM). The optical accuracy was obtained by ray tracing, and compared with that of the imported PMs. Through two years of running of the 100m-long parabolic trough, it has been proven that the PMs in this design have good resistance to wind. In addition, the glass backing plate is able to protect 1.1 mm silver mirror from the attack of sand, so the PMs in this design have good anti-sandstorm performance. Therefore, this kind of PMs is suitable for windy and sandy environment condition of areas that fit in with solar thermal power in China, and it should be one of the options for PMs in future parabolic trough solar power plant of China.