Paris heat network size and reach

The Paris heat network spans approximately 530 kilometers of pipelines and serves nearly a million people, heating a quarter of the city's buildings. It is the second-largest heat network in Europe and has been in operation since 1927.

Heat sources and sustainability

Nearly half of the heat supplied by the network comes from burning waste, with 46% in 2023 and 45% in 2022. This waste is burned in three Syctom plants across Île-de-France, and the heat generated is used to supply the network. The remaining heat mix in 2023 included gas (39.3%), coal (6.5%), and biomass (6%).

Innovations in heat recovery

Since 2025, the Saint-Ouen plant has started using heat from its smoke to preheat water drawn from the Seine before it is turned into steam. This innovation helps improve the network's efficiency and sustainability. According to the CPCU, the network's operator, 50.7% of the energy used in 2024 came from renewable and recovered sources.

Network coverage and infrastructure

The network connects buildings in Paris and 16 neighboring communes, heating about a third of Parisian social housing, 40% of tertiary buildings, and all hospitals. The buildings connected to the network do not have boilers or fuel storage, relying instead on a closed-loop system where steam transfers heat in sub-stations before cooled water returns to power plants for reheating.

Ownership and growth of the network

The CPCU, which has operated the network since its creation in 1927, is a mixed economy company owned 66.5% by Engie and 33.5% by the City of Paris. It produces about 8 million tons of heat annually and has continued to expand, connecting 134 new buildings in 2024.

Future management and investment plans

The CPCU's current concession ends in December 2026, and the City of Paris has selected the Dalkia-Eiffage-RATP consortium as the new operator, beating Engie. The new contract, valued at 15 billion euros over 25 years, includes a plan to invest 3.4 billion euros to increase the share of renewable energy from 50% to 76%. The City will own the power plants through a new mixed economy company, with 49% public ownership and 51% by Dalkia. Critics have raised concerns about the speed of the contract award, which was made just four months before the municipal elections.