5. Thermal Modeling of Active Solar-Distillation Systems

The coupling of a semi-transparent photovoltaic (PV) module with a conventional solar water collector in a single unit generates a new concept of PVT technology, and it can be considered a hybrid PVT concept. In this case, approximately 15–20% of the incident solar energy is converted into electrical energy, and the rest of the solar energy—approximately 80%—is absorbed by the PV module’s absorber plate, which generates thermal energy. Water as a thermal energy carrier is used for harvesting the generated thermal energy. The extraction of thermal energy using water or air as a medium in the system (by lowering the temperature) enhances the efficiency of the PV module. In active solar-distillation systems, this external thermal energy is transferred to the basin of the integrated solar still. The electrical energy of the PV module is used to run the mechanical water pump for circulation of the fluid in the forced mode of operation. In this chapter, thermal modelling of different active solar-distillation systems coupled with (a) N-flat plate collectors, (b) N-evacuated tubular collectors, and (c) N-compound parabolic concentrator collectors is discussed in detail.