Work has started in Dilsen-Stokkem on Green Turtle, GIGA Storage’s first and largest energy storage facility in Belgium. The former zinc factory site of the 'Société Anonyme de Rothem' on the Rotem industrial estate will be the location for this project. Green Turtle will consist of 640 Tesla Megapack 3 batteries with a power output of 700 MW and a storage capacity of 2800 MWh. The installation will be directly connected to the Belgian high-voltage grid and, according to current planning, will be commissioned at the end of March 2028.
Preparatory earthworks and roadworks commenced in mid-August. This will be followed by the installation of the batteries, cabling, and high-voltage installations. The site is secured with CCTV surveillance and fencing. Additionally, a zone of 26 650 m2 is being planted with native vegetation around the energy storage facility.
Tesla was selected as the EPC partner and is responsible for the engineering and construction of the project, the supply of the Megapack 3 batteries, and long-term maintenance. The civil works are being carried out by contractor STADSBADER CONTRACTORS, commissioned by Tesla.
From the permitting phase onwards, GIGA Storage takes the surrounding environment into account. During the realisation of Green Turtle, attention continues to be paid to the impact on the neighbourhood. Disruption caused by the works is limited as much as possible. Construction traffic may temporarily cause some inconvenience, but here too, the aim is to minimise the impact. The toad mating season is also taken into consideration. In accordance with the ecological protocol, the animals are carefully relocated to a toad pond.
Moreover, GIGA Storage strives for sustainable solutions. Green Turtle uses cobalt-free LFP (lithium iron phosphate) batteries. This technology combines safety and a long lifespan with a lower dependence on critical raw materials. Furthermore, innovative concrete is used for construction that absorbs carbon dioxide (CO2) during the curing process, thereby further limiting the climate impact of the structure.
The CO2 released during the works will be offset as soon as the installation is operational. Six months after commissioning, the CO2 emissions from construction will have been offset. For Green Turtle energy storage, this concretely means that approximately 665 794 tpy of CO2 emissions will be avoided starting six months in. This is comparable to the emissions of about 250 000 petrol cars.
After nearly 60 years, the former zinc factory site on the industrial estate is once again being given a future-oriented economic purpose.
“This site has a long industrial history and was of great significance to Dilsen-Stokkem for many years,” said Mayor, Sofie Vandeweerd. “It is wonderful that a place so strongly connected to our industrial past is now being filled with economic activity again, but this time focused on the energy supply of the future.”
Green Turtle will be situated right next to Elia's 380kV Van Eyck-Gramme high-voltage line. The operator of the Belgian high-voltage grid is constructing a new high-voltage substation at the Rotem industrial estate, to which Green Turtle will be directly connected.
Green Turtle will temporarily store surplus electricity, for example from solar panels and wind turbines. When the demand for electricity exceeds the supply, that energy can be fed back into the grid. At peak times, the installation can supply an amount of electricity equivalent to the daily consumption of approximately 385 000 households.
The storage capacity is also made available to Elia and market parties that help keep the electricity grid in balance and reduce grid congestion. In this way, large scale energy storage makes it possible to integrate more renewable energy while simultaneously strengthening security of supply.
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