Climate neutrality of the French energy system: overview and impact of sustainable aviation fuel production

Temporarily accepted

Reducing CO2 emissions from sectors such as aviation, shipping, road transport and chemical production is difficult but necessary. Although these sectors will most likely continue to rely on carbon-based energy carriers, they are expected to gradually move away from fossil fuels. To do this, the dominant option is to use alternative carbon sources, such as biomass and CO2 from carbon capture, to produce non-fossil carbon vectors (biofuels and e-fuels). However, the limited availability of biomass and the variable nature of other carbon sources require a comprehensive assessment of the trade-offs between potential carbon applications and existing sources. It is then essential to understand the origin of carbon used in sustainable aviation fuel (SAF) to understand the implications of aviation defossilization for the energy system. Furthermore, SAF production implies profound changes to the energy system, which are quantified in this work. This study uses the linear cost optimization tool Energyscope TD to analyze the overall French energy system, including transport, industry, electricity and heat sectors, while ensuring net greenhouse gas neutrality. A new method for modeling and quantifying carbon flows in the system is introduced, allowing for a comprehensive assessment of greenhouse gas neutrality. This study highlights the importance of meeting clean energy requirements and implementing carbon dioxide removal measures as key steps towards achieving climate neutrality. Indeed, to achieve climate neutrality, 1046 TWh of electricity production from non-fossil sources is needed. Furthermore, the findings highlight the critical role of efficient coal valorization and biomass energy, proving that fuel production by combining biomass and hydrogen is optimal. The study also offers valuable insights into the future costs and impacts of SAF production on air travel from France. Namely, the European ReFuel-EU law would increase the price of airline tickets by +33% and would require 126 TWh of hydrogen and 50 TWh of biomass to produce the necessary 91 TWh of jet fuel. Finally, a discussion was held on the implications of the SAF production assumption.