In France, CO2 emissions from the energy consumption of buildings is a structural issue. Finding solutions to that problem is essential for a successful energy transition. In France, gas consumption in commercial and residential buildings accounts for over 2.5 times the historical national imports of Russian natural gas. With costs at more than €80 per MWh next winter, it is imperative that we massively reduce the energy needs of buildings.

In an op-ed piece for the business and finance newspaper Les Echos, Benjamin Fremaux and Pâris Mouratoglou offer innovative solutions to reduce energy consumption and lower dependency on Russian gas. One of these solutions is “geostorage”, which draws on the ground’s isothermal properties. A bit like a thermos, this technology stores heat in the summer to use it in the winter and stores cold in the winter to use it in the summer. With water-to-water heat pumps, the aim is to capture the thermodynamic energy waste known as “waste heat” produced by heating and air-conditioning systems.


What’s more, geostorage is much quicker to set up and responds to the urgent need to reduce energy needs. Without further delay, we should take advantage of the solutions at our disposal to sustainably achieve energy efficiency, in summer and winter, without reducing user comfort.


With this solution, owners or investors can decarbonize buildings under acceptable financial terms, with a return on investment in less than 20 years excluding subsidies, or 10 years accounting for the currently available subsidies of €70 per square meter (Fonds Chaleur and energy savings certificates (CEE) in France).