Enervis Battery Storage Index: German BESS revenues rose further in April amid higher PV output and Middle East tensions

For the past year, enervis has published a monthly Battery Storage Index based on historical market data, highlighting revenue opportunities for battery energy storage systems. The index reflects revenue potential from participation in both the intraday and balancing power markets. It reports the achievable revenues for each month over the past 13 months.

New revenue figures for April 2026

After the already strong March, the positive trend in achievable BESS revenues in Germany continued in April. Revenues increased to around €17,100 per megawatt, representing an increase of approximately 26% compared to March and around 14% above the level observed in April 2025. Market conditions remained broadly similar to the previous month, although volatility became even more pronounced. While persistently high gas prices resulting from the current situation in the Middle East continued to drive elevated daily peak prices, the further increase in PV generation simultaneously led to stronger intraday volatility and more attractive arbitrage opportunities for battery storage systems. In particular, April saw three pronounced periods of strongly negative intraday prices, during which prices temporarily fell several hundred euros per MWh below zero. In addition, very low day-ahead prices of below -400 €/MWh were observed on 26 April at around 2 p.m. At the same time, the upward trend in prices for Frequency Containment Reserve (FCR) and negative automatic Frequency Restoration Reserve (aFRR) continued, further supporting higher achievable revenues.

General trends

Monthly achievable revenues have fluctuated considerably over the past 13 months. The maximum was reached in May 2025 at €19,100 per megawatt per month, while the minimum occurred in December 2025 at €5,700 per megawatt per month.

Battery revenues tend to be higher during the summer months. This is primarily due to strong photovoltaic generation during these months combined with comparatively lower overall electricity demand. In addition, conventional generation capacity is seasonally less available during summer, partly due to maintenance activities and potentially lower efficiency of gas-fired power plants at high temperatures. Wind availability is also typically lower during summer compared to winter or autumn months. As a result, short-term feed-in fluctuations or forecast deviations in PV generation during summer months lead to greater market volatility. This is directly reflected in more intensive trading activity in the intraday market.

Over the past twelve months, battery storage revenues averaged just above €12,600 per megawatt per month (approximately €151,700 per megawatt on an annual basis).

Expected revenues for 2026

Analogous to the approach used for the historical analysis, the Enervis Battery Storage Index also provides a forward-looking perspective. Based on our current power price forecasts, the operation of a typical stand-alone battery storage system is modelled for the year 2026.

The projection of achievable revenues continues to be based on our Current Efforts Q2/2026 scenario; no update of the scenario was carried out this month. The forecast revenues currently amount to €164,600 per megawatt. This is about 9% above the average achievable revenues of the past twelve months. The storage parameters have been kept unchanged.

Methodological explanation: The Enervis Battery Storage Index shows the monthly net revenues that can be achieved historically and in the future in Germany for a 1 megawatt capacity and 2 megawatt hours storage volume (2 hours) battery storage system. The storage system was modeled with a use restriction of 1.5 cycles per day, a maximal depth of discharge of 90%, a technical availability of 97% and a round-trip efficiency of 87%. The index takes into account participation in the following markets: Intraday, Frequency Containment Reserve (FCR) and automatic Frequency Restoration Reserve (aFRR). Imperfect foresight and no revenues from aFRR energy are modeled. The respective prices of the markets for the historical analysis are taken from publications of the transmission system operators and EPEX-Spot. The future outlook is based on the same modeling and parameters and prices from the current Enervis power price scenario Current Efforts Q2/2026.

Further information:

If you are interested in a more detailed analysis and the full report, you can request it here.

About the authors:

Mirko Schlossarczyk – Managing Director of enervis energy advisors is an experienced energy market expert. His consulting focus is on electricity price forecasts, electricity market scenarios and the asset valuation of BESS.

Jonas Anthonioz – Consultant at the energy economics consultancy enervis energy advisors, where he is responsible for battery storage-related topics. In addition to his usual tasks in revenue assessment and profitability analysis of battery storage projects, he developed the enervis BESS Index and the associated BESS Index Report.