Experimental investigation of graphene-based nanofluid enhanced photovoltaic/thermal system: Energy and exergy analysis

• PV/T-enhanced finned-serpentine channel and nanofluid is examined experimentally. • The PV/T performance was assessed considering several energy and exergy aspects. • The PV/T electrical efficiency is increased by about 16 % using 1 % of GnP/water. • Thermal and electrical exergy efficiencies improved by up to 15.5 % and 31.6 %, respectively. The performance of photovoltaic (PV) modules is significantly influenced by the operating temperature, the higher temperature the lower module efficiency. The primary objective of this study is to design, fabricate, and evaluate a photovoltaic/thermal (PV/T) system equipped with a finned-serpentine channel, utilizing water and graphene nanoparticle (GnP/water) with 0.25 %, 0.5 %, 0.75 %, and 1 % concentrations as coolants at Reynold number equals to 1250. The PV/T system’s performance was assessed by analyzing its energy and exergy, focusing on electrical, thermal, and exergy efficiencies. The results revealed that the PV/T system achieved electrical efficiency increments of 4.5 %, 7.6 %, 9.8 %, 13.9 %, and 15.5 % with water and NFs with 0.25 %, 0.5 %, 0.75 %, and 1 % concentrations, respectively. Furthermore, the thermal efficiency was improved by 1.4 %, 1.8 %, 2.3 %, and 2.5 % for the increased nanofluids (NFs) concentrations. The exergy efficiencies exhibited significant gains, with electrical and thermal exergy efficiencies improving by up to 15.5 % and 31.6 %, respectively, compared to water. These results highlight the substantial cooling potential of NFs to enhance the PV module’s performance, which positively improves PV-related applications.