Comparative Analysis of Thermodynamic Performances of a Linear Fresnel Reflector Photovoltaic/Thermal System Using Ag/Water and Ag-CoSO4/Water Nano-Fluid Spectrum Filters

Abstract

Renewable energy represented by solar energy has played an important role in the transformation of the energy consumption structure of the world. This study describes and studies a hybrid photovoltaic/thermal (HPVT) system using a linear Fresnel reflector concentrator (LFRC) and nano-fluid spectrum filter (NFSF). The method of designing the HPVT system is provided. Ag/water and Ag-CoSO4/water NFSFs used for this HPVT system were prepared and experimentally tested. Optical analysing results indicate that the optical efficiencies of the PV cell module (PVCM) and NFSF are 0.7556 and 0.9053 under the condition of 0.3° solar tracking error (STE), demonstrating good adaptable capacity to the STE. Moreover, the operating performances of the HPVT system using different NFSFs are compared. The comparison results demonstrate that compared with the Ag/water NFSF, the introduction of CoSO4 can enhance the thermal performance but decrease the photovoltaic efficiency of the HPVT system. When the Ag-CoSO4/water (1.2 mg–3 g/130 mL) NFSF is used, the photovoltaic and thermal efficiencies of the whole HPVT system are 0.1366 and 0.4259, and the overall exergy efficiency is 0.209. The exergy efficiency of the HPVT system will be improved if the NFSF temperature is increased appropriately or if the external convection heat transfer coefficient and environment temperature are reduced.