Producing enough sustainable aviation fuel (SAF) to achieve “net zero” air travel in the UK by 2050 would require “enormous quantities” of the country’s land or renewable electricity resources to maintain flights at today’s levels, according to a new report.
The Royal Society, which is made up of leading scientists, said that the UK will have to resolve “resource and research questions” around the development of alternative options to traditional kerosene-based jet fuel.
The UK government is aiming to achieve net zero on carbon emissions from flying by 2050 through its Jet Zero Strategy and other initiatives, with SAF and alternative types of aircraft technology at the heart of this ambition.
But the Royal Society said that there was “no single, clear, sustainable alternative to jet fuel able to support flying on a scale equivalent to present day use”.
The finding was part of the society’s Net Zero Aviation Fuels report, which has looked at a range of technologies being explored to decarbonise air travel, including biofuels, such as SAF, as well as hydrogen power and synthetic fuels.
When looking at biofuels for aviation, the society said that finding the available land to grow sufficient energy crops and source waste feedstocks to create enough SAF to meet the industry’s needs would be “challenging”.
The report estimated that growing the crops to produce the sustainable fuel necessary for current UK aviation demand would require around half of the UK’s agricultural land.
“Waste feedstocks, including sewage, solid municipal waste or forestry residues, could contribute towards net zero fuel demand, but there is competition from established markets for these feedstocks and significant investment in fuel production and collection infrastructure is required,” said the report.
“While each fuel type has advantages and drawbacks, the findings underscore the challenges of decarbonising aviation, especially when resources are likely to be in global demand for a range of net-zero objectives.”
The society said there were “significant research requirements” in scaling up the use of net-zero fuels including storage, handling and environmental impacts, which required “global co-ordination” in the run-up to 2050.
The Royal Society found that while hydrogen-powered aircraft produced no CO2, its production required “significant” renewable energy as well as “substantial modification” of aircraft and infrastructure.
Using synthetic fuels would produce some carbon emissions but could be used to power existing aircraft. Although creating enough fuel to decarbonise the industry would require an estimated five to eight times the UK’s renewable electricity capacity in 2020.
Professor Graham Hutchings, chair of the report’s working group, added: “We need to be very clear about the strengths, limitations and challenges that must be addressed and overcome if we are to scale up the required new technologies in a few short decades.”
The development of SAF featured as one of the industry’s major developments in BTN Europe’s 2023 Hotlist.