German battery storage research and economic impact

Research in Germany has highlighted the economic and technical implications of battery storage systems. The Fraunhofer Institute for Solar Energy Systems (ISE) released a simulation tool via its Energy-Charts.info platform to model how varying battery fleet sizes and storage durations affect Germany’s day-ahead electricity market.

Simulations of a hypothetical 20 GW battery fleet with two-hour storage durations suggest a significant reduction in price volatility. In such a scenario, the average price difference between the most and least expensive quarter-hour of the day could drop from €130/MWh to €53/MWh, while the frequency of negative prices and extreme price spikes would decrease. The tool also indicates that the market value of solar energy could increase. However, critics point out that these simulations may not account for the high capital costs—estimated between €12 billion and €18 billion—or the potential for slight increases in average annual electricity prices.

Complementary research from HTW Berlin and aquu focused on residential efficiency, revealing large discrepancies in standby power consumption among different battery and inverter systems. Testing showed that idle consumption can vary from 4 watts to 64 watts per hour, representing a 16-fold difference that could cost homeowners approximately 200 euros annually.