Energy Yield Simulation of 3D Curved VIPV Modules

The integration of photovoltaics into the body of vehicles provides many benefits for e-mobility, like inter alia the extension of the driving range, a decreased number of charging cycles per year and the reduction of CO2-emissions of the transport sector. The greatest challenge in integrating photovoltaics in vehicles is the design-related curvature of the modules that the PV modules must follow. The impact of the curvature on the module technology and the energy yield are central research questions that therefore need to be answered. In this study we apply our previously published energy yield model for 3D curved PV modules to simulate the energy yield potential on the roof and hood of different type of cars by considering the module curvature. The curvature of the VIPV module leads to an inhomogeneous irradiance over the module surface. Thus, to an electrical mismatch within the module which can cause high yield losses. We show that the curvature of the roof decreases the yield up to 25 % when using series interconnection of cells. We present an approach to reduce losses that result though the mismatch. We propose the adaptation of the interconnection topology to the curvature by dividing the module into parallel subgroups containing cells with similar azimuth and elevation angles towards the sun. We develop interconnection topologies for roof and hood integrated PV modules based on this approach and simulate the energy yield potential of each design. We show that a reduction of only 3 % - 6 % compared to a horizontal reference can be achieved by using a reasonable low number of subgroups.