Performance assessment of integrated heat pipes and evaporative clay hybrid system for concentrated photovoltaic (CPV) cooling and water harvesting

Solar energy electricity generation with concentrated photovoltaic (CPV) panels delivering substantially higher power output than non-concentrated panels. However, CPVs suffer from excessive heat accumulation and non-uniform temperature distribution, both of which severely impact electrical efficiency and shorten the panels' lifespan. This study explores the implementation of a passive evaporative cooling strategy coupled with heat pipe to mitigate CPV temperature rise. To address this challenge, a novel dual-function mechanism is proposed, enabling efficient CPV cooling while simultaneously capturing and condensing fresh water to minimize evaporative cooling losses. The study evaluates the proposed water harvesting indirect cooling mechanism (WH-ICM) against two alternative cooling strategies: the direct cooling mechanism (DCM), where the evaporative structure is directly attached to the panel's backside, and the indirect cooling mechanism (ICM), which incorporates a heat pipe. The findings revealed that the ICM attained the highest average PV temperature reduction of 45.2 °C, representing a 45.3 % improvement over the conventional PV system. Meanwhile, the WH-ICM followed closely with a 42.3 °C reduction, marking a 42.4 % enhancement. Furthermore, WH-ICM boosted the average PV output power by 36.8 % and improved average efficiency by 30 % compared to the standard PV system. It also harvested 2.87 kg/day.m2 of water, with a consumption of 25.36 kg/day.m2, recovering around 11.3 % of the total water used. Notably, integrating WH-ICM increased the system's daily average overall efficiency to 19.43 %, reflecting a 36.26 % improvement over the conventional PV system, and a 7.7 % and 3.1 % raise compared to the DCM and ICM, respectively.