Design Optimization And Optical Characterization Of A High Temperature Solar Receiver

Concentrated solar power (CSP) is a fast forwarding technology in power generation sector because of its\u27 competitive price, abundance in nature and the most important fact is its\u27 energy storage capability. Among the four types of available CSP technology, central receiver has more potential concerning with high temperature, power block efficiency and levelized cost of energy (LCOE). Other than conventional type of receiver design, the concept of this work is very particular in a sense of its design novelty. National Renewable Energy Laboratory (NREL) come up with a new concept of high temperature solar receiver called near black body (NBB) receiver. This receiver design requires high specular reflective surface in its\u27 front section at operating temperature 150C. High specular reflective surface refers to mirror finished surface. However, this specular reflective surface application is for high temperature solar receiver, the surface needs to be durable from thermal cycling, oxidation and environmental effect. This mirror finished specular surface helps to penetrate the sunlight inside the hollow tube and hence increase receiver\u27s efficiency. But at such operating temperature and environmental condition, optical properties degradation rate is high. So to protect this mirror surface a thin layer of SiO2 has been deposited by sol-gel method on top of electroplated silver coating. To obtain a rigid thin film structure, sol-gel procedure has been tested extensively by varying most dominant sol-gel parameters. Endurance test has been performed in the furnace at 150C for 1000 hours