Wärtsilä has begun construction of a 50 MW / 100 MWh battery energy storage system in central-eastern Belgium for Gramme Storage 1. The order was recorded in Q2 2025 and the project will operate under Belgium’s Capacity Remuneration Mechanism to provide ancillary grid services. Commissioning is planned for Q2 2027, with the facility designed to support grid reliability and integration of variable power generation.
PROJECT SNAPSHOT
| Field | Details |
|---|---|
| Project | Gramme 1 |
| Location | Central-eastern Belgium |
| Developer | Gramme Storage 1 (Kallima Energies) |
| Technology Provider | Wärtsilä |
| Capacity | 50 MW / 100 MWh |
| Technology Platform | GridSolve™ Quantum2 with GEMS software |
| Contract Type | Engineered Equipment Delivery (EEQ) + Long-term Service Agreement |
| Market Participation | Belgium Capacity Remuneration Mechanism (CRM) |
| Order Booked | Q2 2025 |
| Expected Completion | Q2 2027 |
Finland-based technology company, Wärtsilä has commenced the construction of a 50 MW / 100 MWh battery energy storage system (BESS) in central-eastern Belgium. The project is being excecuted for Gramme Storage 1 and is developed by Belgium-based energy developer, Kallima Energies. The agreement was secured in Q2 2025 and site completion is scheduled for Q2 2027.
The Gramme 1 project marks Wärtsilä’s first energy storage installation participation in Belgium’s Capacity Remuneration Mechanism (CRM), which supports grid services, such as frequency and voltage management. By participating in the CRM, the 50 MW system will be eligible to provide dispatchable capacity and ancillary services to support system reliability as renewable generation increases in the national energy mix.
The facility will deploy Wärtsilä’s GridSolve Quantum2 battery energy storage platform, integrated with the company’s Grid Energy Management System (GEMS) digital energy management system. The combined hardware and software configuration is intended to optimize performance, manage dispatch, and enable real-time response to grid conditions. The system is designed as a fully integrated, standalone solution capable of operating across multiple market applications, including balancing and reserve services.
Wärtsilä will execute the project under an engineered equipment delivery (EEQ) contract. The agreement includes defined performance guarantees, with a separate long-term service agreement covering asset management and operational support. This structure provides operational oversight and performance assurance throughout the project lifecycle.
With the addition of the Gramme 1 project, Wärtsilä’s cumulative energy storage portfolio in Europe exceeds 2.7 GWh. The company continues to supply battery storage systems across multiple European markets under various delivery and service models aligned with national regulatory frameworks. Construction of the project is in underway at the Belgian site with commissioning scheduled prior to 2027 commercial operations.
Guillaume Poncelet, Managing Director of Kallima Energies, stated that the project with Wärtsilä strengthens dependable and flexible energy infrastructure in Belgium. He added that the battery energy storage system is designed to deliver ancillary services for grid balancing and system stability.
David Hebert, Vice President of Global Sales Management at Wärtsilä Energy Storage said that the partnership with Gramme Storage 1 supports Belgium’s energy security and grid stability. He added that Wärtsilä’s technology will enable the site to deliver ancillary services for system reliability.Top of Form