System impacts of aviation fuel switching

This report summaries the findings of a workshop convened by the National Engineering Policy Centre (NEPC) on Tuesday 14 September 2021 to discuss how plans for a decarbonised aviation sector via ‘fuel switching’ may impact on wider energy, transport and environmental systems. By examining the implications of fuel switching in these wider systems, the aim was to assist officials and others considering options for decarbonising flight by identifying impacts, key interdependencies, systemic risks and potential opportunities for efficiency and speed in decarbonising aviation.

The alternative fuels considered in this workshop were: i) battery electricity, ii) hydrogen, iii) biofuels, and iv) e-fuels and syn-fuels.

These low/zero-carbon fuels do not, and will not, exist in isolation from the energy, transport and environmental systems. Therefore, this workshop took a wider view of impacts on other systems to provide a broader understanding of the practical implications of large-scale use of those fuels. The scale and pace of the ‘fuel switching’ necessary to decarbonise aviation in line with UK legal obligations raises important questions about standards, safety, regulation, cost, transition process and timing. It also raises the potential for knock-on impacts on energy, land and transport systems, with the potential to increase the demand upon them or change what is required of them; for example in terms of energy supply, transport system integration, safety or logistical requirements, or new environmental risks.