Energetic, exergetic, economic and environmental analysis of a photovoltaic/thermal system equipped with thermoelectric generators

In photovoltaic panels, the solar energy not converted into electricity turns into thermal energy, raising the panel's temperature and reducing efficiency. One potential solution to harness this thermal energy is to use a photovoltaic/thermal (PV/T) system equipped with thermoelectric generators (TEGs). In this study, we present a new Matlab/Simulink model of a PV/T-TEG system and evaluate its annual performance from energetic, exergetic, economic, and environmental perspectives. We compare the results across three locations (Macapá, Almería, and Wien) and various TEG configurations. Furthermore, the possibility of nighttime energy production by TEGs is investigated. The findings indicate that the annual electricity production of the PV/T-TEG system can increase by up to 6.6 % compared to the PV/T system, with an increase in exergy efficiency of up to 6.2 % if only electrical energy is considered. However, installing TEGs is economically disadvantageous and less efficient energetically and exergetically when considering the thermal energy of the PV/T system as a useful output. Lastly, the findings show that a small amount of electrical power can also be produced at night.