Development of a fully coupled concentrator-spectral splitter-thermal-electrical model with evaluation of electrical uniformity for full-spectrum photovoltaic/thermal systems

Concentrated photovoltaic/thermal (PV/T) systems encounter challenges of limited spectrum utilization and localized overheating PV panels. Nanofluids with beam filtering provide a dual-function solution by converting part of the spectrum into electricity while absorbing the remainder as heat. This study developed an innovative coupled concentrator-spectral beam splitter (SBS)-thermal-electrical model for a parabolic trough concentrated system integrated with an Ag-water beam splitter. A novel method for quantifying performance uniformity was proposed, and key thermal and electrical metrics were systematically evaluated across various concentration ratios (CRs), with and without the splitter. Model validation showed a 5.52 % relative error in electrical performance, proving the model reliability. In systems without a splitter, the localized overheating and inefficiencies of the PV panels intensified with higher CR, despite thermal performance gains. Compared with the CPV/T system, the quality and efficiency of the thermal energy were 3.3 and 9.52 times greater at a CR of 10 in the system with a splitter, and the PV efficiencies reaching 30.70 %. Additionally, the temperature and PV efficiency uniformity showed improvements with respect to the conventional CPV/T system of 75.47 % and 68.20 %, respectively. This study demonstrated that the SBS-CPV/T system exhibited exceptional performance and stability for practical applications.