Review of sputter deposited mid- to high- temperature solar selective coatings for flat plate/evacuated tube collectors and solar thermal power generation applications

摘要

Solar energy is the most abundant source of renewable energy. Solar radiation is converted into thermal energy and subsequently to electrical energy by solar thermal concentrating systems. Concentrated solar power systems use solar absorbers to convert sunlight to thermal electric power. Solar absorbers are coated with solar selective coatings with high solar absorptance and low thermal emittance. Spectrally selective coatings which are stable up to temperatures  400C (in air and vacuum) have been developed in the past. However, in order to increase the efficiency of solar thermal power plants, solar selective coatings with high thermal stability are required. In recent years, great advances have been made in the field of solar selective coatings with high solar absorptance and low thermal emittance at higher temperatures (T > 450C). Transition metal based solar selective coatings in particular, have emerged as novel high temperature solar selective coatings which can be used for solar thermal power plants for electricity generation. Further research is currently underway in order to increase the thermal stability of the coatings and subsequently improve the efficiency of solar thermal power plants. We present a comprehensive review of sputter deposited mid- to high-temperature solar selective coatings used for solar thermal applications. This report also describes in detail about the commercially available sputter deposited solar selective coatings for flat-plate/evacuated tube collector and solar thermal power generation applications. The worldwide scenario of parabolic trough power plants which are in operation and, under development is discussed in brief.