Effects of Operational Strategies on Performance and Costs of Electric Energy Storage Systems

An important technical issue of electric energy storage systems (EESSs) is the operational strategy (OS). It strongly influences performance, costs and therefore profitability of the systems and is still insufficiently discussed. This paper investigates the influences of different types of OS on performance and costs of EESSs, using the example of a residential building with photovoltaic installation (PV) and a small combined heat and power plant (CHP). The function of the EESS is on the one hand to increase the self-consumption of the building and on the other hand to reduce the peaks and volatility of the feed-in caused by the PV and CHP systems, which are conflicting goals. To reach those goals, four levels of OS are defined. For each level a control system is designed and analyzed for an exemplary building.