German power generation company RWE has started construction on a large-scale battery storage facility at its power plant locations in Neurath and Hamm, Germany.

Featuring 690 lithium-ion battery blocks, the new facility will have a 235MWh storage capacity and can operate at a maximum capacity of 220MW for over an hour.

The battery energy storage system (BESS), which involves nearly €140m investment, is anticipated to supply balancing energy to the grid starting in the second half of 2024.

It will take excess power from the electricity grid and feed it back into the system when required, to maintain the required grid frequency.

The facility will take electricity into the storage system when electricity prices are low and will feed out when prices are high.

RWE generation CEO Roger Miesen said: “As the proportion of renewables in the electricity mix increases, so does the need for flexible battery storage systems.

“They balance out fluctuations in the electricity grid in seconds, which means they are the key to a reliable electricity supply.

“In terms of size and technology, the new large-scale battery storage facility in Neurath and Hamm is setting standards throughout Europe.”

RWE will install batteries with a total capacity of 80MW (84MWh) in Neurath, on a site covering around 7,500m² of area, which entails about €50m of the total investment.

The company will install batteries with a total capacity of 140MW (151MWh) at Hamm-Uentrop, covering an area of 14,000m², involving about €90m of the total investment.

RWE plans to virtually integrate the new facility with its power stations in Germany to optimise the use of its power station portfolio in the country.

The networking will allow the company to select whether the storage units need to work alone or in conjunction with other power stations to supply balancing energy.

Furthermore, the company said that it is directly tracking the detailed planning, modelling, system integration and commissioning of the project, entirely on its own.

RWE Power Board member Lars Kulik said: “With this battery storage facility, RWE is providing a major boost to structural transformation in North Rhine-Westphalia.

“By making practical use of the existing locations and grid connections, we are making the traditional power plant sites of Hamm and Neurath important partners for renewables.”