Numerical study of a photovoltaic/thermal hybrid system with nanofluid based spectral beam filters

This study presents a 3-dimensional numerical simulation of a flat-plate photovoltaic/thermal (PV/T) hybrid system using a nanofluid as the solar spectrum filter. A series of parametric studies have been carried out to investigate the module performance by employing different base fluid (water, therminol VP-1 and propylene glycol) - nanoparticle (Ag, Fe3O4 and SiO2) combinations. The present work explores the effects of different nanoparticle concentrations, volume flow rates of applied nanofluids, as well as the solar spectrum intensities on the energetic and exergetic performances of the proposed module. Merit functions for various basefluid or nanofluid based hybrid PV/T systems are also assessed in order to determine their economic feasibility. The results show that the suspension of nanoparticles into basefluids has a considerable influence on the radiative heat fluxes that are absorbed by each component of such system. The selection of basefluid-nanoparticle combination is dramatically affected by the desired energy form, based on the system energetic and exergetic performances. Besides, both the system energy and exergy efficiencies are improved with the increment of solar irradiance, whereas they have a counter tendency by increasing the volume flow rate of working fluid. The employment of liquid absorptive filters in such systems can realize a higher energy output which is 179%-240% of that of a stand-alone PV system.