Exergy analysis of a hybrid PV/T system based on plasmonic nanofluids and silica aerogel glazing

摘要

The photovoltaic/thermal (PV/T) systems can generate thermal and electrical energy simultaneously and make full use of the whole solar spectrum, which leads to a higher hybrid efficiency for solar energy harvesting. In recent years, due to the tunable optical properties and excellent thermal properties, plasmonic nanofluids have great potential in the PV/T systems working as both coolant and an efficient optical filter. In this study, a hybrid PV/T system based on plasmonic nanofluids and silica aerogel glazing are proposed and evaluated for the first time. An optical filter based on plasmonic nanofluids is designed and optimized. Silica aerogel glazing is applied in the PV/T system working as a thermally insulating and optically transparent layer to reduce thermal loss. Both electrical and thermal performances of this system are studied numerically. An exergy analysis is employed to evaluate the performance of this hybrid PV/T system and to compare with standard PV and PV/T systems under different solar concentrations and different environmental conditions. The results indicate that the present PV/T system based on plasmonic nanofluids and silica aerogel glazing can produce more electrical and high-grade thermal exergy. In the concentrated solar systems at C = 10, the exergy output of the present PV/T system is enhanced by 13.3% compared with the traditional PV/T system. The proposed PV/T system shows great potential in the solar energy utilization, especially in the low-flux solar systems.