Clean Tech Flows: Suez and CNRS Reinvent Wastewater

Suez and CNRS join forces to cut emissions and reimagine wastewater treatment across Europe

11 Apr 2025

Suez and France’s National Centre for Scientific Research (CNRS) have formed a five-year partnership aimed at cutting emissions and improving energy efficiency in wastewater treatment, as European utilities face tighter environmental rules and ageing infrastructure.

The alliance, announced in April, combines CNRS’s scientific research with Suez’s operational scale. The two groups said they would focus on technologies that remove contaminants more effectively, recover energy from sewage sludge and reduce the carbon footprint of treatment plants, while keeping costs manageable for municipalities.

Rather than upgrading existing systems incrementally, the partners are targeting what they describe as step-change improvements. Wastewater treatment is energy-intensive and accounts for a meaningful share of local government emissions, particularly in large urban areas.

The collaboration builds on more than 30 joint research projects and 14 shared patents developed over previous years. The new phase will emphasise commercial deployment. A pilot project near Bordeaux is testing technology that converts wastewater sludge into biogas, which can be reused on site to lower energy bills and emissions.

“This is no longer theoretical,” said a European utilities analyst. “We’re seeing the kind of research industry synergy that accelerates real change.”

The partnership comes as the European Union tightens standards on water quality and carbon emissions. Utilities are under pressure to modernise facilities built decades ago while limiting increases in consumer tariffs. Industry executives say innovation is essential to meet these goals.

Suez and CNRS have adopted a shared intellectual property model, which they say is designed to balance risk and reward as new technologies are scaled up. Such arrangements remain relatively rare in public-private research partnerships in the sector.

Challenges remain, including adapting solutions to different local conditions and ensuring consistent performance at scale. Still, the companies argue that closer integration between research institutions and operators will be necessary if Europe is to meet its environmental targets in water management over the coming decades.