ENGIE has started construction of a new large-scale battery park in Coo, Belgium
ENGIE has begun construction of a new Battery Energy Storage System (BESS) with a capacity of 74 MW/296 MWh at its Coo site in the province of Liège, Belgium. The project will further strengthen Coo's role as a major energy hub in Belgium, which already houses a pumped-storage power plant, solar installations and electric vehicle charging infrastructure. Commissioning is scheduled for early 2028.
Following Vilvoorde, Kallo and Drogenbos, ENGIE is continuing the rollout of its large-scale BESS projects in Belgium. The future battery park at Coo will have an output of 74 MW and a storage capacity of 296 MWh, to store electricity when renewable generation is abundant and feed it back into the grid when demand is higher, delivering power at full capacity for up to four hours.
The project is fully aligned with ENGIE's ENERGIZE 2030 strategy in Belgium, which focuses on developing flexible assets that can support the increasing integration of renewable energy into the electricity system. With the BESS projects already in operation (Vilvoorde 200 MW/800 MWh) or under construction (Kallo 100 MW/400 MWh, Drogenbos 80 MW/320 MWh and now Coo 74 MW/296 MWh) — representing a combined capacity of 454 MW and 1,816 MWh — ENGIE further confirms its position as a leading player in battery energy storage in Belgium.
At the Coo site, the new battery park will complement an already highly diversified portfolio of energy assets, including the Coo pumped-storage power plant (1,080 MW), which has been a cornerstone of flexibility for Belgium's electricity system for decades, as well as solar installations (715 kW, 2,640 photovoltaic panels) and electric vehicle charging infrastructure. The addition of a large-scale BESS will further reinforce Coo's position as a future-oriented energy hub.
Preparatory works on the site began in March 2026. Construction activities began on 3 August 2026, with commissioning planned for early 2028.
Vincent Verbeke, CEO of ENGIE Belgium: "With this new battery park in Coo, we are taking another concrete step in implementing our ENERGIZE 2030 strategy. Flexibility is essential to support the continued growth of renewable energy while ensuring a reliable, affordable and sustainable electricity system. Thanks to its pumped-storage power plant, Coo has long been an iconic energy storage site in Belgium. By adding battery storage capacity, we are further strengthening its role as an energy hub serving the country's energy transition."
Key figures
- 74 MW of power
- 296 MWh of storage capacity
Indicative project timeline
- March 2026: Preparatory works begin
- 3 August 2026: Start main construction
- Early 2028: Commissioning
Storage at the heart of ENGIE's strategy
With 4.7 GW of storage capacity in operation and under construction in Europe and 10.7 GW worldwide, ENGIE confirms its role as a leading provider of energy flexibility. In July and August alone, the Group expanded its European storage footprint through a series of strategic acquisitions, construction starts and commissioning of projects in Poland, Belgium, Romania, Portugal, the Netherlands, Spain and the UK totaling 1.1 GW/3.3 GWh.
Together, these advancements represent an important step toward the Group’s ambition of developing a diversified portfolio of renewable generation and storage assets totaling 95 GW of installed capacity by 2030.
Olivier Desclée
