Experimental and numerical investigation on photovoltaic/thermal characteristics of an integrated PV/T-PCM system with metal fin and heat exchange pipe

In this work, a synthetical photovoltaic/thermal (PV/T) system incorporating phase change materials (PCMs), metal fin and heat exchange pipe was proposed. The influences of fluid flow velocity, PCMs thickness and heat exchange pipe position on the photovoltaic/thermal characteristics were investigated. The work demonstrated that the average photovoltaic conversion efficiency for the synthetical PV system (PV/T-PCM) respectively increased by 40.4 %, 9.8 %, and 10.1 %, compared with the traditionary PV, PV-PCM and PV/T systems. Meanwhile, the all-day output electric energy of PV/T-PCM system also enhanced by 205.85, 71 W·h and 50.2 W·h, respectively. Increasing water flow velocity from 0.02 m/s to 1 m/s led to a maximum increase of 1.91 % in the average photovoltaic conversion efficiency, 9.14 % in the average photothermal conversion efficiency and 2.12 % in the all-day output electric energy. The PV/T-PCM system owning 35 mm thick PCMs reached the highest average photovoltaic conversion efficiency of 11.26 %. The highest photothermal conversion efficiency of 70.7 % was reached in system with 45 mm thick PCMs. The average photovoltaic and photothermal conversion efficiencies for PV/T-PCM system respectively enhanced by 3.91 % and 11.08 % by optimizing the distance between heat exchange pipes and PV back plate.