Breaking ground on Belgium’s largest battery energy storage project

Work is officially underway on Green Turtle, GIGA Storage’s flagship battery energy storage project in Dilsen-Stokkem, Belgium. As Owner’s Engineer, Tractebel is supporting the development of this landmark facility, which will become the largest battery storage installation in Belgium and one of the largest in continental Europe, helping accelerate the country’s energy transition.

A major milestone has been reached for the Green Turtle battery energy storage project,  with the start of construction works at the Rotem industrial site in Dilsen-Stokkem. Developed by GIGA Storage Belgium, the project will feature 640 Tesla Megapack 3 batteries, delivering a power output of 700 MW and a storage capacity of 2,800 MWh. Once commissioned in March 2028, Green Turtle will be directly connected to the Belgian high-voltage grid and will be capable of storing and supplying renewable electricity equivalent to the daily consumption of approximately 385,000 households.

Tractebel is Owner’s Engineer on this major sustainability initiative

As Owner’s Engineer, Tractebel provides multidisciplinary technical expertise throughout the project lifecycle. Our specialists support GIGA Storage on key aspects including battery energy storage systems (BESS), grid connection, electrical engineering, civil works, fire protection and overall project development. Since the design phase began in 2024, Tractebel has been helping ensure the technical robustness, safety and long-term performance of what will become a strategic asset for Belgium’s electricity system.

Engineering one of Europe’s most ambitious battery projects

Construction activities began with preparatory earthworks and roadworks in August 2026, and will continue over the next eighteen months. The project is being delivered by Tesla, which is responsible for the engineering, procurement, construction and long-term maintenance of the facility, as well as the supply of the Megapack 3 batteries. Civil works are being carried out by Stadsbader Contractors. Once operational, Green Turtle will strengthen grid stability by storing surplus renewable energy when production exceeds demand and releasing it back to the network when needed.

Advancing Belgium’s energy transition responsibly

Beyond its scale, Green Turtle also stands out for its strong sustainability credentials. The project uses cobalt-free lithium iron phosphate (LFP) battery technology, reducing reliance on critical raw materials while enhancing safety and durability. During construction, measures are being taken to limit environmental impact, including the creation of more than 26,000 m² of native vegetation and the implementation of ecological protection measures for local wildlife. The project is expected to avoid approximately 665,794 tonnes of CO₂ emissions annually once operational, making a significant contribution to Belgium’s low-carbon energy future.