French energy technology company Elax Énergie has secured €30 million in funding from Noria and Crédit Mutuel Impact, through the Fonds Révolution Environnementale et Solidaire. The capital will support the company's effort to turn millions of residential electric water heaters into a flexible, distributed thermal battery for the national grid. Elax Énergie, founded in 2021 and based in Paris, has already equipped nearly 100,000 homes with its connected control devices.
Turning Water Heaters Into Grid Flexibility
The company addresses a growing challenge in France, where renewable energy output is increasingly volatile and electricity demand must shift to periods of abundant supply. In 2025 alone, France curtailed 3 TWh of renewable electricity because consumption and export capacity were insufficient at times of peak production. Elax Énergie's solution optimizes electric water heating, which currently accounts for between 19 and 24 TWh of annual consumption, or around 5% of French electricity use.
A Large, Overlooked Flexibility Resource
Electric water heating already represents one of France's largest flexible loads, with 15 million homes equipped with storage water heaters. By comparison, the entire French electric vehicle fleet consumed 4 TWh in 2025, according to the company. Elax Énergie argues that these devices, historically developed around off-peak nuclear power, can now be repurposed to absorb solar and wind variability.
A Pragmatic, Industrial Scale Solution
The connected thermostat is designed and manufactured in Lannion, France, and can be installed in about 20 minutes without major building work or changes to occupant habits. It delivers 20% to 25% annual savings on hot water production while detecting limescale buildup, enabling predictive maintenance, and extending equipment life. The company reports that its technology does not compromise comfort and generates flexibility that can be monetized on electricity markets.
Expanding Beyond Social Housing
With the new funding, Elax Énergie will accelerate its historic deployment among social housing providers, where more than 100 landlords already use the system. It will also enter two new strategic markets: the electrification of collective boiler rooms and a national network of tradespeople called Elax Pro for private households. The collective heating offer aims to shift up to 50% of gas based production to electricity without adding management complexity.
Macroeconomic and Employment Effects
At national scale, electrifying France's 38 million homes for hot water could raise electric water heating demand to 53.2 TWh, while flexible consumption could avoid imports of 24 TWh of gas and 7.3 TWh of fuel oil. This shift could improve France's trade balance by between €1.3 billion and €1.6 billion per year, according to the company. Elax Énergie also plans to recruit 30 additional employees by the end of 2027 in research and development, engineering, operations, and commercial roles.
Leadership Perspectives
Thomas Tirtiaux, CEO of Elax Énergie, said the energy transition will not be won only through heavy construction or increasingly expensive equipment, but also through pragmatic, immediately deployable tools. He emphasized that millions of water heaters must become dynamic thermal batteries serving renewable energy, while protecting household purchasing power. Nadia Bouzigues of Crédit Mutuel Impact and Christophe Guillaume of Noria both highlighted the solution's positive climate and social impact, especially for social housing tenants.
The €30 million round positions Elax Énergie to scale a proven French industrial solution at a critical moment for grid flexibility. By combining consumer savings, maintenance intelligence, and demand response, the company aims to turn an overlooked residential asset into a cornerstone of a decarbonized and sovereign electricity system. Its expansion into collective heating and private homes could significantly broaden the technology's impact across France.