In the heart of Merksem, Belgium, three stormwater discharge pumps stand as silent guardians against the growing threat of extreme rainfall. Their job: to prevent flooding in the surrounding area by rapidly evacuating excess water from the sewers during heavy downpours. But what happens when the power grid fails during a storm? Traditionally, Aquafin relied on diesel generators to keep these pumps running for at least four hours. Yet, as climate change intensifies and sustainability becomes a priority, the need for a cleaner, more resilient solution has never been clearer.
The Spark of Innovation: A Sustainable Shift
Aquafin’s commitment to sustainability and the goals of the ResNRJwater project sparked a bold idea: replace fossil-fuel-based backup systems with a Battery Energy Storage System (BESS). This innovative approach not only ensures the pumps remain operational during power outages but also transforms the system into a flexibility asset for electricity markets. By actively managing energy, the BESS generates economic value while supporting grid balance and stability. A win - win for both reliability and sustainability.
Smart Design for Critical Moments
At the core of the BESS is a smart control algorithm that integrates real-time weather forecasts with energy management. When heavy rain is predicted, the system reserves sufficient battery capacity for the stormwater pumps. Aquafin sends a digital rainfall signal to the Energy Management System (EMS), which then reduces or halts market trading to prioritize emergency readiness. This seamless integration of weather data and energy management ensures that the BESS is always prepared for critical moments.
From Tender to Reality: A Journey of Collaboration
The journey from concept to implementation has been a testament to collaboration and innovation:
- June 2025: The tender process was successfully completed, marking the first step toward turning the vision into reality.
- December 2025: With the BESS under assembly, the project gained momentum, and the placement of the information panel symbolized the official start of this groundbreaking investment.
- May 2026: The BESS is installed at the treatment plant and connected to the local electricity grid.
- September 2026: The BESS is expected to be tested, approved and fully operational.
The Big Reveal: A Milestone Achievement
During the 7th ResNRJwater partner meeting in Antwerp, the project partners had the opportunity to visit the BESS in Merksem. This was not just a site visit, it was a celebration of a milestone achievement. The BESS in Merksem is the very first pilot of seven planned installations within the ResNRJwater project. Its successful implementation sets the stage for scaling this innovative solution across the region.
The Road Ahead: Scaling Up for Impact
The BESS in Merksem is more than just a backup power system; it is a proof of concept for a sustainable future. With six more pilots planned, this project is paving the way for a resilient, eco-friendly energy and water management system across Northwest Europe. The integration of smart technology, renewable energy, and cross-border collaboration demonstrates how innovation can address climate challenges head-on.
Join the Journey
The story of the BESS in Merksem is just beginning. Follow the progress of this and other pilots visiting the section OUR PILOTS Or AQUAFIN´s channels. Together, we are shaping a future where sustainability and resilience go hand in hand.