Experimental evaluation of performance of a hybrid solar photovoltaic (PV/T) panel integrated with effective cooling solutions with water base nanofluids and phase change materials

The overall performance of photovoltaic (PV) panels is prejudiced by the operating temperature of the solar cell owing to the absorbed solar radiation. In this experimental study, the in-house hybrid PV/thermal (PV/T) system is designed, fabricated, and parametrically studied for effective and practical applications of the solar panels. The water and water-based nanofluids are used for the active cooling of the PV/T system. The effect of phase change material (PCM) along with the active cooling is also studied, and results are comprehensively discussed. The in-house stable water-based Al2O3 and TiO2 nanofluids are engineered by the two-step method with two different nanoparticle concentrations of 0.05 and 0.1 vol.%. The thermal conductivity and stability of the nanofluids are experimentally measured and discussed to understand their effects on heat transfer from the PV panel. The thermal conductivity of nanofluids is increased with the concentration of nanoparticles in the base fluid. The maximum enhancement of around 30% is observed with Al2O3-water nanofluid at a concentration of 0.1 vol.%. The PV/T system is experimentally simulated in the indoor experimental setup with the solar simulator to provide the variable intensity of solar irradiance from 450 to 1050 W/m(2). The maximum decrement in the panel's temperature is found to be around 25% using both active and passive cooling simultaneously and the electrical efficiency is improved by approximately 10.3% at the 1050 W/m(2). The electrical efficiency has found 13% more with Al2O3-water nanofluid of 0.1 vol% as compared to water cooling at 450 W/m(2). The use of nanofluids also improved the system's thermal efficiency compared to the water, and the maximum improvement of around 10% is achieved with the Al2O3-water nanofluid at 0.1 vol.% concentration. These results are significant for the design of the PV/T system from the application viewpoint.