Abstract
In this work, results of the outdoor exposure campaign of a newly developed hydrophilic anti-soiling coating for concentrated solar thermal power (CSP) mirrors are presented. The material was exposed for nearly two years under realistic outdoor conditions and the influence of two different cleaning techniques was evaluated. Mirror samples were analyzed during exposure and their reflectance and cleanliness were measured. The performance of the anti-soiling coated mirror samples was compared to conventional uncoated silvered-glass mirrors. The coatings showed appropriate anti-soiling and easy-to-clean behavior, with a mean cleanliness gain of 1 pp and maximum values under strong soiling conditions of up to over 7 pp. Cleanliness of the coated samples stayed higher throughout the whole campaign before and after cleaning, resulting in lower soiling rate compared to the reference material. Taking into account these values and supposing a threshold for cleaning of 96%, the number of cleaning cycles could be decreased by up to 11%. Finally, the coated material showed negligible degradation, not exceeding the degradation detected for the reference material.
Highlights
Concentrated solar thermal power (CSP) plants are integrated by large reflector surfaces that concentrate the direct normal irradiation (DNI) onto a receiver, where available solar energy is converted to useful thermal energy [1]
Cleaning the solar field implies high operation and maintenance (O&M) costs [4] and creates an important issue in areas with water scarcity, which normally match with high DNI availability zones, where CSP plants are typically located
As the whole outdoor exposure campaign produced a lot of data, these are separated into several groups
Summary
Concentrated solar thermal power (CSP) plants are integrated by large reflector surfaces that concentrate the direct normal irradiation (DNI) onto a receiver, where available solar energy is converted to useful thermal energy [1]. Cleaning the solar field implies high operation and maintenance (O&M) costs [4] and creates an important issue in areas with water scarcity, which normally match with high DNI availability zones, where CSP plants are typically located. “self-cleaning” or “easy-to-clean” coatings) are becoming an attractive approach [5,6,7]. This technology is used in a variety of products nowadays, with glazing products being the foremost area of application [8]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
