RWE officially begins construction of Germany's largest battery storage facility

Construction has begun in Germany on the country’s largest battery storage facility, with an installed capacity of 400 MW and the ability to supply electricity for almost 2 hours. The facility is expected to help Bavaria cope with fluctuating renewable energy generation and ensure grid stability. Current plans call for the batteries to start operating at the site of a decommissioned nuclear power plant in early 2028.

German energy company RWE announced that it has officially begun construction of Germany’s largest battery storage facility. The facility, with a total output of 400 MW and a capacity of 700 MWh, will be built at the Gundremmingen site in Bavaria. The company will invest around EUR 230 million (approximately CZK 5.6 billion) in the technology.

“Gundremmingen remains a key energy site in Bavaria. In addition to the new battery storage facility, plans are also in place to build a 55-hectare solar park and a gas-fired power plant. The battery storage facility will stabilise the grid when there is no wind and when the weather is overcast. Bavaria, Germany’s most economically successful federal state, needs a great deal of energy. Many thanks to RWE and all its employees for their tremendous commitment here on site,” said Markus Söder, Minister-President of Bavaria.

The battery storage facility will consist of more than 200 containers containing approximately 850,000 lithium iron phosphate battery cells. RWE says that, thanks to advanced controls and ultra-fast inverters, the batteries will be able to respond to grid conditions within milliseconds. The company plans to bring the facility into commercial operation in early 2028.

A replacement for nuclear power?

The battery storage facility is also notable because it will be built at the site of the decommissioned Gundremmingen nuclear power plant. It had three boiling water reactor units, two of which, built in the 1980s and with an output of more than 1,300 MW, generated electricity until 2017 and 2021, respectively. Alongside construction, decommissioning work is also under way at Gundremmingen and will continue until at least 2030. RWE says it still employs around 400 people at the site.

“The energy system of the future requires high-capacity energy storage. By building Germany’s largest battery energy storage facility in Bavaria, an attractive region for energy production, we are sending a strong signal. Gundremmingen demonstrates our ongoing commitment to making consistent use of our sites, and this new storage facility is just the beginning,” added Markus Krebber, CEO of RWE AG.

RWE says it operates battery storage facilities with a combined capacity of around 1.2 GW worldwide, with a further 2.7 GW of projects under construction. In June this year, in neighbouring Netherlands, it commissioned an ultra-fast battery capable of providing synthetic inertia to the grid.