Tilt Angle and Orientation Impact on the Techno-economic Performance of Photovoltaic Battery Systems

Abstract

The techno-economic analysis investigates the impact of tilt angle and orientation on the production profile of a rooftop solar generator and the related performance of a photovoltaic battery storage system for single family houses at a specific location in Germany. The calculations are model-based and take into consideration the consumer load profile, technical and economic photovoltaic battery storage system parameters as well as the framework of regulations. The parameters “share of self-consumption”, “degree of autarky”, and “economic efficiency in terms of levelized cost of electricity” make up the focus of the modelling results. It is concluded that self-consumption and degree of autarky are strongly and inversely related. In terms of system design, a trade-off has to be made between aiming for high self-consumption and a high degree of autarky. Key findings from the modelling results reveal that a south orientation gives the highest degree of autarky and the lowest levelized cost of electricity, but with the lowest share of self-consumption as well. For rooftops oriented towards east/west, an interesting possibility could be to split the total installed capacity (equally) between the two orientations. This makes it possible to benefit from the high self-consumption of the east orientation and the high degree of autarky of the west orientation. In general it has to be considered that the optimum orientation strongly depends on the consumer load profile. Finally, the results show two opposite impacts that depend on orientation when switching from a tilt angle of 30° to 45°. For a south orientation, the degree of autarky is increased, while for west and east orientations, self-consumption increases.