Investigation of electricity, and hydrogen generation and economical analysis of PV-T depending on different water flow rates and conditions

Abstract

In this paper, the electricity and hydrogen generation performance of a system contains a cooled photovoltaic-thermal (PV-T) panel, a parabolic trough solar collector (PTSC), and a proton exchange membrane (PEM) for investigation thermodynamically. The proposed system is also evaluated with respect to energetic and exergetic efficiency. Meanwhile, the water, whose temperature rises by cooling the PV-T, is sent to the PTSCs to reach a higher temperature. Then, it is stored in a storage tank for domestic use. This parametric study is carried out for two different operating conditions. Firstly, the flow rate of the water used to cool the PV-T is gradually increased from 5 g/s to 50 g/s and the simulations are made according to these mass flow rates. Also, an economical analysis of the PV-T is found for these ten mass flow rates, Secondly, the efficiency of the system is determined by changing the ambient temperature from 0 °C to 30 °C under 400 W/m2 solar radiation and by fixing the cooling water flow rate to 50 g/s. All the analyses of the system are made utilizing the Engineering Equation Solver. It is aimed to enhance the hydrogen production performance of the system by increasing the electricity production of the PV-T by removing the excess heat of the solar cells with the water flow. As the flow rate of the cooling water increased, the electrical energy generated by the PV-T increased, so the highest electricity production is achieved when the flow rate was 50 g/s. Also, while the cooling mass flow rate is increased from 5 g/s to 50 g/s, the payback time of PV-T decreases from 8.093 to 7.734 years. The electricity produced is delivered to PEM and hydrogen was produced by electrolysis of water heated by PTSC. As a result, it is obtained that the electricity and hydrogen generation of the system is higher in the summer months than in the other nine months. Accordingly, it is found that while 351.1 g of hydrogen is produced in July, only 144.1 g of hydrogen could be produced in January. On the other hand, it is found that the amount of electricity and hydrogen produced by the system decreases as the ambient temperature increases. However, it was found that the electricity and hydrogen production performance of the system increased when the wind energy coming to the PV-T's surface increased from 1 m/s to 5 m/s.