Idex to initiate geothermal and waste heat project in Levallois, France.

Low-carbon energy company Idex has unveiled an urban heating initiative in Levallois, located in the Hauts-de-Seine region of France. This innovative project will integrate geothermal heating with a waste heat recovery system sourced from a data center, with operations expected to commence by 2029.

Idex plans to invest EUR 70 million in the initiative, which will receive EUR 15 million in support from the French Ecological Transition Agency (ADEME). The project will be executed through SAS EnR, a joint stock company focused on renewable energy. Idex and the city of Levallois will serve as partner shareholders in the development company.

“This significant project in Levallois exemplifies our dedication to a tangible energy transition and sustainable solutions for local communities,” stated Benjamin Fremaux, President of Idex.

“We take pride in contributing our geothermal expertise to help the city achieve decarbonization and energy independence while ensuring controlled costs for consumers. This partnership with the City of Levallois and Global Switch also serves as a testament to how data centers can facilitate the energy transition in local communities when integrated into circular economy frameworks.”

The new geothermal heating facility will utilize thermal waters from an aquifer, anticipated to reach temperatures of 60 °C, sourced from a well to be drilled beneath the Louison Bobet stadium. This will provide an estimated output of approximately 90 GWh annually. Additionally, 28 GWh of heat will be generated from the waste heat recovery system at the Global Switch data center.

Together, the 120 GWh from this hybrid system will supply over 75% of the energy needed for the Kalita district heating network. It is projected to lower the average heating costs by up to 30% once fully operational. For public buildings in the city, this system could generate annual savings of around EUR 650,000.

The waste heat recovery system at the Global Switch data center is set to be operational by the latter half of 2027. Preparatory studies and regulatory processes for the geothermal project commenced in 2025, while well drilling is expected to occur between 2026 and 2027. Construction of the plant will begin in 2028, with heat supply anticipated to start by 2029.

“Levallois is making a pivotal move in its environmental and economic strategy,” noted Agnès Pottier-Dumas, Mayor of Levallois. “Our city is leading the charge in the energy transition, providing direct benefits to its residents. This groundbreaking project with Idex merges ecology, innovation, and purchasing power. By utilizing our local resources, we are securing our energy future while sustainably managing community expenses.”

While numerous geothermal projects are underway to power data centers, the model being developed in Levallois represents a distinctive collaboration between geothermal energy and data centers as joint providers of renewable heat.