Performance analysis and comparison between bifacial and monofacial solar photovoltaic at various ground albedo conditions

Abstract

This paper analyses and compares the performance between a bifacial and a monofacial PVsystem based on the tests conducted at Heriot-Watt University, UK. The module's performance was observed on different ground reflective surfaces: concrete, white tiles, soil, and white pebbles. The rear side irradiance and bifacialenergy gains are analysed. The power output is examined for a sunny and cloudy days, and yearly energy mapping is shown. Correlation studies are performed, and empirical model are developed between (i) clearness index and rear irradiance gain: (ii) rear irradiance gain and bifacial energy gain; (iii) total irradiance and power output. Based on the annual rear irradiance gain analysis, the highest gain range is found for white pebbles and white tiles ground surface (>30 % gain) and lowest for soil surface within the 5 %–10 % range and for concrete, >20 %. Regardless of the ground reflective surface, the probability is low that the bifacial energy gain is more than 30 %. Finally, a case study is discussed to perform a sensitivity analysis of a bifacial PV project's Levelized cost of electricity (LCOE). The sensitivity analysis shows that by using an enhanced ground albedo surface, the LCOE of the bifacial PV project can be reduced to 7.15p/kWh. The results show consistency with simulations output ran in PVSyst for different locations across the UK and the reported bifacial gain worldwide.