Electrical and thermal performance of bifacial photovoltaics under varying albedo conditions at temperate climate (UK)

Abstract

Bifacial photovoltaics (bPV) provide an advantage over their traditional monofacial counterparts as they can utilise solar radiation incident on both the front and rear side of the module, allowing for increased energy production. While this is an advantage on the side of bPV, the amount of energy produced by the rear side of the bPV panel can vary greatly depending on the inclination and azimuth of the panel as well as external climatic and ground albedo conditions. This paper aims to analyse the electrical and thermal performance of bPV under varying albedo conditions, using two different materials: grass, and a reflective material. It also contains an example of bifaciality testing under real-world conditions. Several experiments were conducted to evaluate the electrical performance and the temperature distribution of the bPV panel under different weather conditions at the UK location and then the results were compared with the single diode model of bPV. Furthermore, a bPV panel temperature model has been developed for the temperate climate condition of UK. The results show that the open circuit voltage of the system increases with irradiance up to around 800 W/m2, at which point it decreased due to the increased PV system temperature. The normalised efficiency for the PV system under different conditions were also evaluated, which showed that the bPV module was most efficient under diffuse irradiance conditions, encouraging the use of the bPV technology in the UK.