Clean heat from wastewater
Reference: Amiens Énergies
At a glance
How Amiens Énergies is turning wastewater into sustainable district heating - powered by Innomotics motors. With six high-capacity ammonia heat pumps, driven by 24 compact Innomotics SD motors and frequency drives, the system generates 18 MW of clean heat, supplying 26,000 homes and saving 41,100 tons of CO₂ every year.
The Challenge
- Decarbonizing the district heating network with renewable and recovered energy
- Using treated wastewater as a sustainable heat source
- Achieving >70% renewable energy share while maintaining grid stability
- Integrating large heat pumps into existing plant infrastructure
- Ensuring reliable motor performance in tough industrial conditions
The Solution
- Six ammonia heat pumps (R717) delivering 18 MW at 85 °C
- Powered by 24 compact, converter-driven Innomotics SD motors
- Heat recovered from 8.5 million m³ of treated wastewater per year
- Modular system scalable for future expansion
The Benefits
- 41,100 tons of CO₂ emissions saved annually
- 26,000 homes supplied with renewable district heating
- >70% renewable and recovered energy in the heating mix (target: 80% by 2026)
- 18 MW of sustainable heat generated from wastewater recovery
- Strong contribution to Amiens’ path toward climate neutrality
Reliable motors for a pioneering project
Amiens Énergies is the first single-operation mixed economy company (SEMOP) in France’s energy sector — a partnership between the City of Amiens, ENGIE Solutions, and Banque des Territoires. Its mission: decarbonize the district heating network with a smart, sustainable energy mix.
At the heart of this project is a commitment to renewable and recovered energy. Thanks to the combined expertise of ENGIE Solutions and its partners, Amiens’ network has transformed — reaching more than 70% renewable and recovered energy today, with a target of 80% by 2026.
For the Amiens energy flagship project, reliability and performance were essential. Mayekawa selected Innomotics motors for their durability, high energy efficiency, and proven compatibility with Mayekawa industrial heat pump systems.
Harold Dick, Commercial Director, Mayekawa France
Heat from wastewater – Powered by Innomotics
In collaboration with Mayekawa, Innomotics supplied 24 high-performance SD motors for six large ammonia heat pumps (R717) installed at the Ambonne wastewater treatment plant. The system delivers a total installed power of 18 MW at 85 °C, recovering thermal energy from treated wastewater - a pioneering example of circular economy and sustainable urban heating. Each heat pump operates with two low-stage and two high-stage compressors, all driven by Innomotics SD motors ranging from 160 to 355 kW.
Designed for demanding industrial environments, these motors provide the efficiency, reliability, and robustness required for continuous year-round operation.
Wastewater heat recovery – A model for the future
Amiens Énergies has transformed its heating network into one of the most sustainable in Europe. With an installed capacity of 140 MW, including 72% renewable and recovered energy, the network:
Delivers 160 GWh of clean heat annually
Supplies 26,000 households via a 75 km pipeline
Saves 41,100 tons of CO₂ per year
