Sustainability contribution of hybrid solar collector towards net-zero energy buildings concerning solar cells wasted heat

Abstract

Sustainable communities require emerging innovations to fulfill the energy needs of urban societies. Renewable energy systems are the most significant trend in net-zero energy buildings (NZEBs) that serve sustainable development. Due to their consistent power generation, standalone hybrid solar photovoltaic/thermal (PV/T) systems are currently in reasonable demand in the building sector. This study adopted a special design of the hybrid solar collector utilising a combination of water and air simultaneously as a working fluid (combi-PV/T), considering the waste heat generated from classical polycrystalline photovoltaic (PV) modules that negatively affect the building's sustainability. The main comparison parameters considered between the examined combi-PV/T and PV modules are the waste heat, solar cell surface temperature, exergy efficiency, and sustainability index. The experimental result confirmed the effectiveness of the combi-PV/T compared to the classical PV module. The results showed that the waste heat generated by the combi-PV/T module was lowered by 77.6 %. Besides, the average solar cell surface temperature of the PV module decreased by 30.6 % in the combi-PV/T module from 53.6 °C to 36.4 °C. Exergy efficiencies for combi-PV/T and PV ranged from 12.6 to 35.3 % and 4.4–6.8 %, respectively. Moreover, the sustainability index values were in the range of 1.15–1.8 and 1.03–1.06, respectively. Obtained findings indicated that the combination of hybrid solar PV/T systems has an efficient sustainability contribution and the potential to subsidise sustainable building construction towards NZEBs.