Energy, exergy, economic, and environmental (4E) analyses of bifacial concentrated thermoelectric-photovoltaic systems

A concentrated photovoltaic-thermoelectric (CPV-TE) system could utilise the full solar spectrum for electrical energy generation. However, the output performance of the conventional CPV-TE system is low due to the high thermal resistance associated with the TE module that raises the surface temperature of the PV. This study presents comprehensive energy, exergy, economic, and environmental (4E) analyses of two conventional unifacial CPV-TE models and two bifacial CTE-PV models. The bifacial models receive solar energy from two directions. The results reveal that at a concentration ratio of 60, the highest electrical energy and exergy efficiencies of 32% and 35%, respectively, are obtained from the bifacial concentrated segmented thermoelectric-heat sink-photovoltaic (CSTE-HS-PV) model. The annual CO2 savings due to the energy generated by the CSTE-HS-PV, CTE-HS-PV, and CPV-HS-TE are 202 kg/year, 119 kg/year, and 13 kg/year, respectively. Moreover, the payback period (PBP) of the CSTE-HS-PV, CTE-HS-PV, and CPV-HS-TE models are 8.4 years, 10.5 years, and 45 years, respectively. Finally, the levelized cost of energy (LCOE) of the CSTE-HS-PV, CTE-HS-PV, and CPV-HS-TE models are 0.36 $/kWh, 0.55 $/kWh, and 5.06 $/kWh, respectively. Based on the 4E analysis, the CSTE-HS-PV model is found to be superior to the other state-of-the-art models.