Getting Prices for Prosumers Right? Incentivizing Investment and Operation of Small-scale PV-Battery Storage Systems Through Prices, Charges and Levies

Abstract

We assess how the design of retail prices, grid fees and levies for household prosumers affects the attractiveness and resulting operation of small-scale photovoltaic battery storage systems (PVBSS), using a detailed modeling approach applied to a case study of six households in Germany. The selected pricing schemes and reform proposals are evaluated regarding the investment attractiveness for the prosumer and the impact on system-oriented operation, considering both market and grid integration. We show that the current business models for PV and PVBSS are only exist because they are based on avoiding the need to purchase electricity from the grid and thus avoiding paying taxes and levies on consumed electricity. Introducing time-variable pricing schemes or price components increase the value of PVBSS for the customer and the market, but lead to a less grid-friendly operation. It is shown that the term “system-oriented operation” should be defined carefully, since under the analyzed incentives, the two objectives included in system-oriented operation (market and grid integration) do not necessarily go hand in hand, sometimes even contradicting one another. Both the tariff design and the design of single tariff components have a considerable impact on the attractiveness and the resulting system integration of PVBSS and should be evaluated thoroughly to avoid unintended outcomes.