Projects
Harmignies BESS

Harmignies BESS

Harmignies BESS is one of Europe’s largest battery energy storage installations, delivering 75MW of output and 300MWh of four-hour duration storage. Located on an established industrial site beside Elia Group’s high-voltage substation in Harmignies, the project strengthens one of Belgium’s most critical grid nodes as the country accelerates its renewable energy rollout.

Sector	Battery Storage
Developer	Energy Solutions Group
Project	Harmignies BESS 75MW/300MWh
Location	Mons, Belgium
Scope of Work	Twenty-two 4.4MVA Wilson MV Transformers

Operational since autumn 2025, the system provides high-availability flexibility services, supports renewable curtailment reduction, and delivers fast-acting stability to the Belgian electricity network. With enough capacity to deliver 75MW continuously for four hours, Harmignies BESS plays a major role in supporting the region’s long-term grid resilience.

The project also sits close to the 50MW/200MWh Wallonia BESS site, where we have previously supplied fourteen Wilson MV Transformers and a Wilson Power Transformer, marking Harmignies as the latest milestone in our ongoing contribution to Belgium’s energy storage landscape.

The project, located in an area that was previously a cement factory, consists of eighty two Tesla Megapacks 2XL connected to the grid through twenty two 4.4MVA Wilson T2 Ecotrans® Large Distribution Transformers.