German battery storage developer ADS-TEC Energy expects to receive the building permit shortly for a 1 GW / 4 GWh four-hour battery storage project at the Pulverdingen substation in Markgröningen, Baden-Württemberg. Grid connection is planned for 2029, according to reporting by Renewable Energy Industry.
Capacity doubled to 4 GWh
The company doubled the planned storage capacity from about 2 GWh to 4 GWh while keeping the planned power capacity unchanged at 1 GW, shifting the project from a two-hour to a four-hour duration profile. Longer duration is increasingly favoured in Germany because it captures more of the spread between midday solar surpluses and evening peaks.
ADS-TEC is in talks to sell a majority stake in the project company to finance construction. Projects of this scale typically require investments ranging from the upper hundreds of millions of euros to around €1 billion, which is beyond the balance sheet capacity of most developers.
Germany's gigawatt-class pipeline
The Markgröningen project joins a growing list of announced large-scale German batteries. BW ESS's facility in Klostermansfeld is planned at up to 5.7 GWh, while LEAG and Fluence are building a 4 GWh project in Jänschwalde. Both of those projects are already under construction, whereas the Markgröningen building permit is still pending.
According to IEA data cited in the report, Europe's utility-scale storage installations more than doubled in 2025 to around 4.6 GW of power capacity. Germany had 1,292 battery storage systems connected at medium-voltage level or higher, with about 3.6 GW of power capacity and 6 GWh of storage capacity in operation in August 2026.
Tolling model gains ground
Alongside merchant gigawatt projects, tolling structures are spreading in the German market. Uniper has signed a seven-year tolling agreement with Stadtwerke Lippstadt for a planned 20 MW / 42 MWh battery in Roßfeld. The battery will be owned by Lippstädter Ladesäulen GmbH, a wholly owned subsidiary of Stadtwerke Lippstadt, which receives a fixed fee for granting Uniper use of the system, while Uniper handles marketing and commercial optimisation and adds the flexibility to its trading portfolio.
Supply chain caveat
The scaling story comes with a supply-chain warning. LFP batteries were used in more than 90% of newly installed stationary battery storage systems worldwide in 2025, with cells coming almost exclusively from China. The European Commission's Joint Research Centre cites limited European supply of raw materials and battery materials and higher production costs, leaving European cell production for stationary storage underdeveloped.
Source: Renewable Energy Industry; ESS News
This article was assisted by AI analysis. Please refer to the original source for official information.