RWE has started construction of a 236 MW/470 MWh BESS at the former Hambach lignite mine near Niederzier in North Rhine-Westphalia, Germany, with commercial operation scheduled for 2027 (RWE press release, 28/07/2026).
The project comprises 128 lithium-ion battery containers, the first of which has already been delivered following site preparation works that began in late 2025. The BESS is expected to provide grid-balancing services, including frequency regulation, and has been designed to deliver additional grid-support functions such as synthetic inertia in the future.
According to RWE, the Hambach facility forms part of its broader battery storage expansion programme in Germany, where the company is currently building around 1.7 GW of storage capacity.
The Hambach mining area is already being repurposed for renewable energy projects. RWE has previously commissioned three solar parks with a combined capacity of around 50 MW and a 4 MW/8 MWh BESS at the site. The company is also developing a nearby 15 MW solar project alongside an additional 80 MWh battery storage facility.