Techno-economic comparison of a schedule-based and a forecast-based control strategy for residential photovoltaic storage systems in Germany

In Germany, the huge integration of small photovoltaic (PV) systems into the distribution grid during the past years leads to power quality issues due to the intermittent generation and reverse power flow in periods of low demand. To decrease this impact, different solutions are being investigated. The scope of this paper is to compare different strategies to control the charge power for residential PV storage systems for different load curves and to decide which might be the economically most profitable strategy. For this purpose, three different PV storage system control strategies were analyzed using MATLAB®to perform 1-year simulations on a minute step base. Measured input data from a PV system in the south of Germany were combined with four measured (extreme) load profiles and a standard load profile to conduct a sensitivity analysis. Performance indicators, such as self-consumption ratio (SCR), self-supply ratio (SSR), and share of losses ratio (SLR), were used to compare the different control strategies. Furthermore, an economic analysis of these results was performed to obtain the profitability of every control strategy and to determine the most profitable strategy, considering the household owner’s benefits.