A First in Brussels: Using the Senne River Water to Heat the ONSS Building
By installing two heat pumps on the Senne, Veolia transforms a Brussels river into a local, decarbonized energy source, while preserving aquatic biodiversity.
With the rise of renewable energy, terms like wind, solar, and biomass have become familiar. But have you ever heard of aquathermy? In 2025, Veolia BeLux will use the Senne River as a sustainable energy source to power the National Social Security Office (ONSS) building. For the first time at this scale, two heat pumps will harness the river's water to heat a six-story public building, resulting in nearly eliminating gas consumption and an annual savings of 361 tons of CO2. This innovative project offers a new way to produce local, decarbonized energy while protecting aquatic wildlife.
Water as an Energy Source
Did you know? Hidden beneath the streets of Brussels, the Senne River runs through the city and serves as a stable, renewable heat reservoir. Thanks to aquathermy—a technique that uses the heat stored in natural water bodies like rivers or lakes—it’s now possible to harness this energy for heating or cooling buildings. This will soon be the case for the ONSS offices, located above the Gare du Midi, which will benefit from energy captured from the Senne to meet their heating needs.