Net zero aviation fuels: resource requirements and environmental impacts

Aviation is a contributor to global warming, including through the emissions of carbon dioxide and the formation of contrails high up in the atmosphere. Globally, save for the few years of the pandemic, air travel is expected to continue to grow in the future, increasing the impact on climate change unless a close to net zero form of flying can be developed or any residual emissions offset by removals.

If low carbon emission jet fuels are to have a strong positive impact on the UK’s Road to Net zero, it is important that the alternative fuels adopted are truly beneficial to the fight against the climate crisis and do not cause unacceptable collateral ecological damage.

What are the options for net zero aviation fuels?

The report looks at four alternative fuels: hydrogen, ammonia, synthetic fuels (efuels) and biofuels, and examines each option against:

• Equivalent resources that would be required for that option to replace fossil jet fuel,
• Life cycle analysis and non-CO₂ environmental impacts,
• Likely costs,
• Modification or replacements needed to implement the option.

It is evident that all alternative fuel options have advantages and challenges and there is no single simple answer to decarbonising aviation. 

Main conclusions from the net zero aviation report

• Availability and accessibility of sustainable feedstock for all options is a key challenge.
• Further R&D will be needed in the development of the efficient production, storage and use of green hydrogen, ammonia and efuels.
• Further development of LCAs of all alternative aviation fuels is required which will be critical in clarifying emissions across the entire cycle and highlighting key mitigation opportunities.
• R&D is required to understand and mitigate the non-CO₂ climate impacts of all the alternative fuel options.
• A holistic approach with regards to alternative fuel and engine and airframe development will be needed.
• Considerations will have to be made on handling multiple technologies both in the airport and aircraft.
• Staff and crew will need specialised training on handling alternative fuels, and the public will need to be informed about the relevant safety concerns within the airport and aircraft.