RWE announced plans to construct three new battery energy storage systems (BESS) in Germany, with a total installed capacity of approximately 600 MW. The new systems will be built on the site of the Westfalen power plant in Hamm, as part of the company's efforts to support grid stability amid the country's transition to renewable energy.
The battery parks will have a total storage capacity of 1.2 GWh and can discharge their maximum output for up to two hours. When combined with a battery storage system that began operations in February, the Hamm site will eventually have a total storage capacity of 1.35 GWh. This will be sufficient to charge over 23,000 average electric vehicles.
RWE Generation SE's CEO Nikolaus Valerius emphasized the growing need for technologies to balance the grid as renewable energy sources increase. “With the expansion of renewable energies, the need for technologies that can instantly counteract imbalances in the electricity grid is increasing,” Valerius said. “Battery storage systems are ideal for this because they are fast and efficient.”
The planned expansion will make Hamm a key location for battery storage in Germany. “The massive expansion of our storage capacity at the Westfalen power plant will make Hamm the battery storage flagship location of Germany,” Valerius added. “Our facilities will make an important contribution to stabilizing the energy market by efficiently storing surplus energy and feeding it into the grid in a targeted manner – with a dampening effect on electricity prices for consumers and industry.”
The new battery storage systems will cover more than six hectares and involve the installation of over 25,000 lithium-iron phosphate (LFP) batteries housed in 316 overseas containers. The systems will use advanced control technology and rapid inverters to deliver balancing power within milliseconds, a service referred to as instantaneous reserve or inertia.
“Inertia has mainly been provided by rotating masses of turbines, traditionally from coal-fired power plants, but the number of rotating generators is falling due to the rise in renewables,” RWE noted. “Battery energy storage systems can compensate for this loss of inertia.”
The mayor of Hamm, Marc Herter, highlighted the importance of secure storage capacities for Germany's energy transition. “The additional large-scale battery storage facilities on the site of the Westfalen power plant in Uentrop will ensure that the grid remains stable and short-term fluctuations can be balanced out cost-effectively,” Herter said.
Preparatory construction activities have already begun, and RWE plans to have the new battery storage systems operational between 2026 and 2028.
