One of Germany’s largest energy storage facilities is being built near the decommissioned Grohnde nuclear power plant. On March 1, we presented our plans to interested citizens.
Pullach, March 2025: The municipality of Emmerthal near Hamelin in Lower Saxony is becoming a pioneer in the integration of renewable energies into the electricity grid: We will build a battery energy storage system (BESS) in the immediate vicinity of the decommissioned nuclear power plant in the Grohnde district.
“With the large-scale battery, we are helping to make the most of the potential of wind and solar energy, reduce the use of fossil fuel power plants and balance out fluctuations in the electricity grid,” explains GESI CEO Jens Wegmann. Stationary battery storage systems are indispensable for a successful and affordable energy transition because they store surplus electricity efficiently and provide it flexibly – exactly when it is needed.
“Larger than any project realized to date”
On March 1, Wegmann and his team presented the GESI project at the energy fair in Emmerthal town hall. Interested citizens were able to find out about the function and significance of the BESS as well as the technology and timetable (here you can find a report on the event in the Deister- und Weserzeitung newspaper).
The GESI plant will be built on a seven-hectare site near the decommissioned nuclear power plant. With a planned storage capacity of 870 megawatts, it is larger than any large-scale battery project realized in Germany to date. By comparison, the Grohnde nuclear power plant had an output of 1360 megawatts.
Since GESI received the grid connection approval in January, preparations have been in full swing. “Our goal is for the large-scale battery to be connected to the grid in 2028,” says Wegmann. In addition to playing a pioneering role in the energy transition, the BESS offers tangible benefits for the region:
- Efficient use of renewable energies: Surpluses from solar and wind power are stored and used flexibly – with a dampening effect on electricity prices. This takes the scare out of so-called dark doldrums.
- Climate protection: The large-scale battery reduces dependence on fossil fuel power plants – and therefore CO₂ emissions.
- Security of supply: The system balances out fluctuations in the electricity grid, strengthens the local electricity infrastructure and helps to secure the energy supply for citizens and businesses.
- Municipal budget: The municipality can look forward to additional annual trade tax income in the seven-figure range.
“With the project in Grohnde, we are demonstrating that our storage solutions integrate local communities into the energy transition and at the same time offer economic benefits for local residents and businesses,” says GESI CEO Walter Raizner. Thanks to the good cooperation with the municipal decision-makers, Grohnde is “on the right track”.
Due to a lack of storage options, wind and solar parks have to be throttled back or even switched off on sunny and windy days. The GESI project is helping to prevent such losses in future and to make the most of the potential of renewable energies.
