Construction has officially commenced on Belgium’s new flagship battery energy storage project, Green Turtle, developed by Giga Storage. Boasting a 700 MW / 2.8 GWh capacity, the four-hour-duration facility will stand as the country’s biggest battery storage site upon completion, marking a major milestone in Belgium’s energy grid optimisation.
Located at a former zinc factory site within the Rotem industrial estate in Dilsen-Stokkem, Limburg province, the project sits in Belgium’s eastern border area adjacent to the southern Netherlands. Site preparation works started in mid-August 2026, with the official construction launch held on September 17. Commercial commissioning is targeted for late March 2028.
Green Turtle will be equipped with 640 Tesla Megapack 3 units. Tesla takes on the role of engineering, procurement and construction (EPC) contractor, responsible for full-project engineering, construction, battery supply and long-term operational maintenance. The facility’s supporting infrastructure will include 188 medium-voltage and four high-voltage transformers to ensure stable power conversion and operation.
To integrate with the national power network, the project will directly connect to Belgium’s key 380 kV Van Eyck-Gramme high-voltage transmission line operated by grid operator Elia. A brand-new high-voltage substation is being built by Elia at the Rotem industrial estate specifically for this interconnection. Once operational, the project’s full capacity will be accessible to Elia and energy market participants to facilitate grid balancing and mitigate power grid congestion issues.
The project secured full financial closure in July 2026 with a total investment of approximately €700 million. Its funding structure combines debt financing and equity investment: a consortium of ten international and European banks provides €450 million in loans, while the remaining €250 million is funded by InfraVia Capital Partners, Giga Storage’s majority shareholder. The banking consortium includes ABN AMRO, ING, Rabobank, Triodos Bank, Triodos Investment Management, a.s.r., Belfius, Hamburg Commercial Bank, Santander and SMBC.
