Performance investigation on a concentrating photovoltaic thermal system integrated with spectral splitter and absorption heat pump

Abstract

To alleviate the energy consumption crisis and environmental pollutant problems, a concentrating photovoltaic thermal system integrated with spectral splitter and absorption heat pump is proposed. Through solar spectral splitting, the photo-electric and photo-thermal processes are decoupled, which facilitates the cogeneration of electricity and high-temperature heat. Through absorption heat pump, the temperature of geothermal energy is improved by high-temperature solar heat for subsequent utilization. Thus, the efficient utilization of full spectrum solar energy is achieved. To further evaluate the performances, an electric-thermal coupled model is developed and the comprehensive analysis is carried out from energy, exergy and exergoeconomic viewpoints. Results indicate that for an optical window of 400–1300 nm, strong LiBr/H2O solution concentration of 64 %, concentration difference of 5 % and thermal receiver temperature of 438.15 K, the overall energy and exergy efficiency is obtained about 102.14 % and 37.49 %, respectively. Among all components, parabolic trough concentrator is the most inefficient component with energy losses of 123.86 MWh. Highest exergy destruction is observed in the solar cell, accounting for 67.51 % of the total destruction. Moreover, a total exergoeconomic factor of 79.94 % is obtained for the entire system indicating that 20.06 % of the total costs are related to exergy destruction.