Presentation
There is a political and scientific consensus on the two main levers for reducing heating-related emissions: reducing demand and decarbonising heating energy. Demand can be controlled through energy-saving and energy-efficient measures, notably through deep retrofits; decarbonising heating energy requires replacing the most emitting vectors, namely natural gas and fuel oil, with low-carbon alternatives. Considering the major social and political at stake, this Issue Brief aims to identify the levers that will enable the rapid decarbonisation of heating in buildings, as well as the conditions for the success of this transition.
Key Messages
- Replacing heating systems is an integral part of building energy renovation, as is insulating the building envelope: the two are complementary and often inseparable levers, and must be treated as such in public policies.
- Moving away from fossil fuels is essential in order to achieve carbon neutrality in the building sector, and implies a rapid phase-out of fuel oil (by 2030) and a gradual phase-out of natural gas. It therefore seems essential to deepen the political debate on the phase-out of fossil-fired boilers. To avoid ideological deadlocks, this debate should focus on the conditions of acceptability and implementation, distinguishing between measures for new buildings, renovations in existing buildings, and the signals needed to structure the associated supply.
- Hybrid systems (combining gas boilers and electric heat pumps) and biomethane are among the levers for decarbonising heating systems. However, given the limited potential for biomethane in the building sector, and the constraints involved in implementing hybrid systems, these solutions are difficult to generalise, and should be reserved for buildings where the installation of electric heat pumps would be unsuitable.
- Heat pumps are the most energy- and climate-efficient heating system available, provided they are combined with satisfactory insulation of the building envelope. To accelerate their deployment, solutions are needed to the installation constraints specific to certain types of building (condominiums in particular), and paying close attention to the impact on winter electricity peaks and associated CO2 emissions is also necessary.
- In addition to national frameworks, the implementation of local planning for the decarbonisation of heat remains essential to mobilise local energy sources and ensure the coordination of individual and collective choices, particularly for the development of heat networks.
