This article examines the efficiency of various liquid-based solar collectors, focusing on their thermal performance and the impact of selective surfaces on energy absorption. Liquid-based collectors, including flat-plate, evacuated tube, and concentrating collectors, are evaluated for their ability to convert solar radiation into usable thermal energy. Key parameters such as heat transfer efficiency, temperature differentials, and fluid dynamics are analyzed to determine optimal operating conditions. Additionally, the role of selective coatings—designed to enhance solar absorption while minimizing thermal radiation losses—is explored. This research contributes to the ongoing efforts to improve renewable energy systems and reduce reliance on fossil fuels.

Solar energy, liquid-based collectors, efficiency, wind energy, thermal energy, fuel and energy resources, thermal power plants,thermal radiation, renewable energy.

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