Original Title:
Functional coatings for smooth operation and stable performance of flat-type solar panels under various conditions
Languages of Item:
English
Creator:
Zarkadoulas, Athanasios
Konstantaras, John
Stathopoulos, Vassilis
Koukou, Maria
Vrachopoulos, Michail
Affiliation:
Laboratory of Chemistry and Materials Technology, National and Kapodistrian University of Athens, Psachna Campus, Evia, Greece
Energy and Environmental Research Laboratory, National and Kapodistrian University of Athens, Psachna Campus, Evia, Greece
Abstract:
Solar collectors, when exposed to the elements, are vulnerable to factors that lead to
performance reduction such as solid pollutants, dust, and rain. Solar collectors must therefore
operate under harsh conditions while achieving stable performance and high efficiency.
Functional coatings for the glass surface of the collector plate have been proposed as a
solution to aid in the performance stability of solar collectors. In this work, that has been
completed within the framework of “Solar Kit” research project, functional coatings for flat
plate solar collectors have been developed, applied using cold spraying method and have been
tested. The coating sprays do not contain Volatile Organic Compounds (VOCs) because they
are sprayed using water-based emulsions thus reducing the required active substance
concentration and the environmental impact of using VOCs. The effectiveness of the coatings has been validated by contact angle (CA) measurements. Since the coated surfaces concern solar absorber plates, low reflectiveness and high transmittance factors are the key evaluation
parameters for achieving maximum solar radiation absorption and avoid performance
degradation of the solar collector. Measurements for the total reflectiveness and total
transmittance of the coatings have been performed showing that total reflection of the coated
glass is lower that the untreated for up to 6 coating layers while the transmission of the coated
glass is improved for up to 3 coating layers. Thisleadsto the conclusion that up to three coating
layers can be applied to the collector’s glass without affecting its performance while
simultaneously improving its anti-pollution and self-cleaning attributes.
Keywords:
solar energy
solar radiation
solar collectors
Notes:
Περιλαμβάνει βιβλιογραφικές αναφορές:
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Olabi, A.-G. (Ed.), Encyclopedia of Smart Materials, Elsevier, Oxford (2022) pp. 243–
257. https://doi.org/10.1016/B978-0-12-815732-9.00151-0.
