[Nuclear by the Numbers] A Low-Carbon Energy… Even More in France

With the “Nuclear Energy in Numbers” series, RGN sheds light on energy challenges through key data. Today, we focus on CO₂ emissions from different electricity generation methods, both globally and in France.

According to EDF’s Climat Obs’COP 2024 study[1], 56% of the global population believes that nuclear reactors emit a significant amount of greenhouse gases responsible for climate change. In France, this figure drops to 48%, with 25% even believing that nuclear power plants generate a substantial amount of CO₂. However, this is far from reality.

The global figures presented are sourced from the Intergovernmental Panel on Climate Change (IPCC), while the French data comes from ADEME (France’s Agency for Ecological Transition). These results account for the entire energy consumption and emissions across the full life cycle of nuclear facilities. This includes fuel extraction, manufacturing, and transportation, the construction and decommissioning of industrial sites, reactor operation, and waste management.

Thus, the IPCC calculates 12 gCO₂eq/kWh, while ADEME reports 6 gCO₂eq/kWh. EDF’s own 2022 assessmentmeasured French nuclear power at just 4 grams of CO₂ per kWh. While all three figures remain within the same order of magnitude, why is there a two- or even threefold difference between the global and French values?

The Key Impact of the Electricity Mix

The difference is due to the technologies used in uranium enrichment and the electricity mix of each country. In France, uranium enrichment is carried out using centrifugation, a method that is far less energy-intensive than gaseous diffusion. Additionally, the carbon footprint of the enrichment process depends on the electricity mix of the country where it is performed.

France benefits from an electricity mix that is approximately 95% low-carbon. This creates a virtuous cycle, where nuclear power provides low-carbon electricity for the uranium enrichment process, which in turn supplies the nuclear industry itself. ■