For the first time in France, Grundfos and ENGIE are deploying iGRID, an innovative solution designed to optimise urban heat networks in a smarter way.
It’s a strategic step toward smarter, more sustainable energy management. And with early results showing significant reductions in energy grid losses and CO₂ emissions, it’s well on the way towards facilitating the integration of renewable energy sources.
Why traditional heat networks fall short
When ENGIE launched the iGRID pilot project in collaboration with Grundfos, it reflected a shared commitment to innovation and sustainability.
Before the implementation of iGRID, the network faced challenges such as high return temperatures, unnecessary energy losses, and limited flexibility to integrate renewable sources. These inefficiencies not only increased operating costs but also risked customer dissatisfaction.
Traditionally, urban heat networks supply water based on the most demanding consumer, wasting energy for those with lower needs. Water is heated and supplied at the temperature required by the consumer with the highest demand – often the largest building or facility in the network. While this ensures that every customer gets the heat they need, it comes at a cost, with many buildings receiving water that is hotter than necessary.
Designed for real-world impact
iGRID changes that. At its core, it optimises heat distribution by adjusting water temperature to actual demand. By isolating branches of the network and introducing return water via a large mixer, it supplies water at the precise temperature required, reducing losses and optimising efficiency.
Starting this project in Lyon was no coincidence, since the city has long been recognised for its commitment to energy innovation. And the site quickly emerged as the ideal testing ground for iGRID. Featuring a high-temperature, extensive and rapidly expanding heat network, backed by instrumentation that provides precise data, it enables reliable, real-time data that allows you to measure exactly how well iGRID performs.
The site brings together 15 consumers with similar consumption profiles, using both heating and domestic hot water throughout the year. This combination of homogeneity and continuous activity creates an ideal open-air laboratory for testing the robustness and performance of iGRID under varied and representative conditions.
With this project, we aim to demonstrate the effectiveness of the iGRID concept under real operating conditions, with the ultimate goal of validating the approach locally. Then, we can start considering deployment across other heat networks in France and Europe.
Precision and efficiency in every building
The iGRID system is delivered as a compact, pre-configured skid that includes pumps, sensors, valves and an intelligent control cabinet. Leveraging advanced PID control, iGRID continuously adjusts both temperature and pressure in real time to match the specific needs of each building. This dynamic regulation ensures seamless integration and communication with ENGIE’s SCADA platform, optimising the overall performance of the heat network.
One of the most exciting aspects of iGRID is its ability to integrate renewable energy into existing networks. Operating at lower temperatures makes it easier to connect decarbonized energy sources while maintaining overall system efficiency, creating a clear path toward greener, smarter urban heat infrastructure.
Installation is straightforward and efficient, too, with just the hydraulic and electrical connections required on site. This means that the system can become fully operational within just a few hours. Thanks to its open communication protocol, iGRID can easily interface with other systems, while the intuitive user interface automatically adapts operational parameters to changing network conditions, delivering optimal performance with minimal manual intervention.
iGRID T-Zone Skid Version
A new era of urban heating
For ENGIE, iGRID has proven not just to be a triumph in engineering, but a sustainability enabler. By reducing thermal losses and optimising energy flows, it cuts both consumption and CO₂ emissions, all while maintaining high levels of comfort for users. The system also allows existing networks to be densified without increasing production, maximising the efficiency and paving the way for further savings without extra investment.
“Our investment in iGRID was driven by the need to modernise infrastructure, meet climate goals and demonstrate leadership in sustainable urban energy systems. And we feel like we’ve already taken significant steps to achieve that. So, this isn’t just a project – it’s a glimpse into the future of urban energy, and we’re very excited about it,” says Alexis Goldberg, Country Sales Manager, ENGIE Solutions.
This is a glimpse into the future of urban energy.
Lyon’s northern plateau is the first site in France to test iGRID, and we look forward to sharing the results with you in 2026. In the longer term, our ambition is to extend the solution across France’s heat networks and throughout Europe.
Alexis Goldberg (left), Sales country Director, ENGIE Solutions and Martial Archenault (right), Cylergie Manager, ENGIE Recherche & Innovation