Performance evaluation of proposed heat pipe and desiccant materials hybrid systems for water harvesting and concentrated photovoltaic system cooling

Energy and water are essential for human beings' life. Researchers tried to find solutions to face the energy crises and water shortages. Solar energy shows excellent potential to generate electricity using photovoltaic panels and generate water using a desiccant atmospheric water harvester. A concentrated photovoltaic panel offers much -generated power compared with a non -concentrated panel for the same panel area; however, it suffers from the very high temperature and non -uniform temperature distribution on the panel, which causes a significant reduction in the electrical efficiency and reduction in the panel lifetime. Nearly uniform temperature distribution can be obtained using a flat heat pipe, which is integrated into the panel's backside and provides the excess panel heat to the heat sink. The desiccant atmospheric water harvester needs heat to desorb water vapor, which is then condensed and collected. This paper offers two hybrid system configurations that cool the concentrated photovoltaic and generate water by providing the excess heat of the concentrated photovoltaic to the desiccant material. The first configuration is a direct cooling technique where the panel's backside is directly attached to the desiccant. In contrast, the second configuration is an indirect cooling technique where a heat pipe interfaces the panel backside and the desiccant. The system model is presented, solved using MATLAB, and validated. The current study evaluates the influence of the concentration ratio of the concentrated photovoltaic panel, the heat pipe condenser area to evaporator area ratio, the thickness of the desiccant layer, and the desiccant type on the cell temperature, cell electric efficiency, generated power, desiccant uptake, the harvested water per day, and the system overall efficiency. It was found that the maximum average cell efficiency has a value of 13.97% when the concentration ratio is 1, the heat pipe condenser area to evaporator area ratio is 2, the layer thickness is 2 cm, and the system uses the silica gel at the indirect cooling technique configuration. The maximum average power is 212 (W/m2) when the system configuration works on an indirect cooling technique and has a heat pipe condenser to evaporator area ratio = 2, concentration ratio = 4, the layer thickness = 1 cm, and the desiccant is silica gel. The minimum average output power, excluding the naturally cooled photovoltaic panel, is 59 (W/m2) when the system configuration works on the direct cooling technique and has a concentration ratio = 1, the desiccant layer thickness = 3 cm, and the desiccant is zeolite. The maximum amount of the harvested water and harvested water per unit area are 0.75(kg/day) and 12.02 (kg/(day m2)) when the heat pipe condenser area to evaporator area ratio is 2, the concentration ratio is 4, the layer thickness is 3 cm, and the system uses silica gel as the desiccant. The proposed systems of photovoltaic panel cooling and water harvesting are designed for areas with water scarcity or limited water resources.