ENGIE Begins Construction of 74 MW / 296 MWh Coo Battery Park to Expand Grid Flexibility and Renewable Energy Integration in Belgium

ENGIE Begins Construction of 74 MW / 296 MWh Coo Battery Park to Expand Grid Flexibility and Renewable Energy Integration in Belgium

(IN BRIEF) ENGIE has begun construction of a new 74 MW / 296 MWh battery energy storage system at its Coo site in Liège province, expanding one of Belgium’s most important flexibility hubs and advancing the company’s ENERGIZE 2030 strategy. The facility will be able to supply electricity at full power for up to four hours and is scheduled for commissioning in early 2028 following preparatory works that began in March 2026 and the start of main construction on 3 August. The project will complement Coo’s existing 1,080 MW pumped-storage hydropower plant, 715 kW of solar generation and EV charging infrastructure, creating an increasingly diversified energy storage and flexibility site. Together with BESS projects at Vilvoorde, Kallo and Drogenbos, the Coo development will bring ENGIE’s Belgian battery portfolio in operation or under construction to 454 MW / 1,816 MWh. The investment also contributes to ENGIE’s wider storage expansion, with 4.7 GW of capacity in Europe and 10.7 GW worldwide, as the Group works toward its target of 95 GW of installed renewable and storage capacity by 2030.

(PRESS RELEASE) LA DÈFENSE, 4-Sep-2026 — /EuropaWire/ — ENGIE has started construction of a new large-scale Battery Energy Storage System (BESS) at its Coo site in the province of Liège, Belgium, adding 74 MW of power and 296 MWh of storage capacity to one of the country’s most established energy hubs.

The battery park will be capable of storing electricity when renewable generation is abundant and releasing it back into the grid when demand rises. At full output, the system will be able to deliver electricity for up to four hours.

Commissioning is scheduled for early 2028.

The project forms part of ENGIE’s ENERGIZE 2030 strategy in Belgium, which focuses on developing flexible generation and storage assets capable of supporting the growing integration of renewable energy while maintaining reliability and affordability across the electricity system.

Coo joins ENGIE’s growing Belgian battery storage portfolio

The new Coo development follows ENGIE’s other large-scale battery projects at Vilvoorde, Kallo and Drogenbos.

Vilvoorde is already operational with 200 MW / 800 MWh of capacity, while Kallo is under construction with 100 MW / 400 MWh and Drogenbos with 80 MW / 320 MWh.

Together with the new Coo installation, ENGIE’s Belgian BESS portfolio will represent a combined 454 MW of power and 1,816 MWh of storage capacity across projects in operation and under construction.

The company said this continued investment reinforces its position in Belgium’s battery energy storage market and supports the increasing need for flexibility as more variable renewable electricity enters the grid.

Battery project expands diversified Coo energy hub

The battery park will complement several existing energy assets at Coo.

The site already hosts the 1,080 MW Coo pumped-storage hydropower plant, which has provided large-scale flexibility to Belgium’s electricity network for decades.

It also includes solar installations with a capacity of 715 kW, comprising 2,640 photovoltaic panels, as well as electric vehicle charging infrastructure.

The addition of a large-scale BESS will further diversify the site by combining pumped-storage hydropower, battery storage, solar generation and electric mobility infrastructure within the same energy hub.

ENGIE said the combination will strengthen Coo’s role in supporting the flexibility and resilience required by Belgium’s evolving electricity system.

Construction started in August following preparatory works

Preparatory work at the Coo site began in March 2026.

Main construction activities officially started on 3 August 2026, with the project scheduled to become operational in early 2028.

Once commissioned, the battery park will provide 74 MW of power and 296 MWh of usable storage, allowing it to respond rapidly to fluctuations between electricity supply and demand.

ENERGIZE 2030 strategy focuses on flexibility and renewable integration

Vincent Verbeke, CEO of ENGIE Belgium, said the Coo battery project represents another concrete step in implementing the company’s ENERGIZE 2030 strategy.

He said flexibility is increasingly important as renewable generation expands and Belgium seeks to maintain a reliable, affordable and sustainable electricity system.

Verbeke noted that Coo has long played an important role in Belgian energy storage through its pumped-storage facility and that adding large-scale battery capacity will further strengthen the site’s contribution to the country’s energy transition.

ENGIE reaches 4.7 GW of storage capacity across Europe

The project forms part of ENGIE’s wider expansion in energy storage.

The Group currently has 4.7 GW of storage capacity in operation or under construction across Europe and 10.7 GW worldwide, combining battery storage and other flexibility technologies.

During July and August 2026 alone, ENGIE expanded its European storage portfolio through acquisitions, construction starts and project commissioning across Poland, Belgium, Romania, Portugal, the Netherlands, Spain and the United Kingdom.

Those developments represented an additional 1.1 GW / 3.3 GWh of capacity.

ENGIE’s storage investments support the Group’s broader ambition to develop a diversified portfolio of renewable generation and storage assets reaching 95 GW of installed capacity by 2030.

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SOURCE: ENGIE