Positive impact of red soil on albedo and the annual yield of bifacial photovoltaic-systems in Ghana

 The annual yield of bifacial photovoltaic (PV) systems is highly dependent on the albedo of the underlying soil. There is currently no published data about the albedo of red soil in western Africa. In this study, the impact of the albedo of red soil in Ghana on the energy yield of bifacial PV systems is analyzed. A bifacial PV simulation model is created by combining the optical view factor matrix with an electrical output simulation. For an exact simulation, the albedo of red soil is measured for the first time at three different locations in Ghana. The average albedo of any red soil is clearly determined as well as the measurement span including instrumentation uncertainty. Considering these data, a state of the art bifacial PV system with 19.8 % average efficient modules in northern Ghana can reach an annual energy yield of 508.8 kWh/m2 and a bifacial gain of up to 18.3% in comparison to monofacial PV panels. To summarise, red soil in two out of three locations in Ghana shows higher albedo values than most natural ground surfaces and, therefore, positively impacts the annual yield of bifacial PV.