Procurement Process for a Battery Energy Storage System in Antwerp, Belgium
Aquafin is in the process of procuring a Battery Energy Storage System (BESS) for installation at the Merksem wastewater treatment plant (WWTP), located in the east of Antwerp. This system will serve as an alternative to traditional diesel emergency generators, offering a more sustainable solution.
Project Scope
At WWTP Merksem, three stormwater discharge pumps (SWA pumps) must be activated during heavy rainfall to prevent flooding in the surrounding area. To ensure uninterrupted operation during power outages, an emergency power supply is essential. Previously, Aquafin has relied on diesel generators at other locations, but the decision has now been made to implement a BESS, eliminating reliance on fossil fuels.
The BESS will serve as a backup power source for the SWA pumps in exceptional cases - specifically, when mains power fails during heavy rainfall. To maximize the investment, the battery will also be used strategically to participate in electricity market flexibility trading.
Before heavy rainfall, sufficient battery capacity must be available to ensure the SWA pumps can be activated if needed. Aquafin will provide a digital signal indicating expected heavy rainfall, which will trigger a partial suspension of market trading. This signal must be integrated into and processed by the contractor’s proposed Energy Management System (EMS), making it a critical component of the project.
Current Status
The
selection phase began in the summer of 2024 with over ten interested parties
qualifying. In close collaboration with VEB and its engineering consultants,
significant effort has been dedicated in recent months to developing a detailed
specification covering the design, installation, monitoring, and maintenance of
the BESS. This week, Aquafin received proposals from several candidates, which
will now be reviewed and evaluated based on the award criteria in the coming
weeks.

System outline: BESS working in bad weather conditions when mains power fails (copyright Aquafin)