On June 16, RWE officially brought its first inertia-ready battery energy storage system (BESS) into commercial operation at its power plant in Moerdijk, the Netherlands. This marks the first system of its kind to go live within the Central European power grid.
The system features an installed power capacity of 7.5 megawatts (MW) and an energy storage capacity of 11 megawatt-hours (MWh). Equipped with fast-response control technology and grid-forming inverters, the system can inject or absorb power within milliseconds, providing critical support to grid stability. This service, known as “inertia,” is essential for maintaining frequency balance in modern power networks.
As the share of variable renewable energy sources grows, keeping the grid stable has become increasingly complex. Inertia, traditionally provided by the spinning masses of turbines in fossil fuel power plants, acts as the grid’s fastest source of balance. The new battery system replicates this function using advanced technology.
Nikolaus Valerius, CEO of RWE Generation SE, stated:
“Our new plant in Moerdijk demonstrates that ultra-fast battery systems can now deliver inertia—an essential grid service once provided only by conventional power stations. As large fossil fuel plants are phased out, systems like this will be vital to ensuring grid stability.”
The Moerdijk BESS is part of the OranjeWind project, a joint offshore wind initiative led by RWE and TotalEnergies off the Dutch coast. The facility uses advanced lithium iron phosphate (LFP) battery technology and high-speed inverters, representing a blueprint for RWE’s broader global expansion of battery storage capacity.
In parallel with its commercial operation, the Moerdijk plant has also entered a two-year pilot phase. During this time, RWE will work closely with transmission system operator TenneT to develop technical standards and grid compliance protocols for inertia-capable battery systems.