Will Sustainable Aviation Fuels Take Off?
In Sheffield, researchers at the University of Sheffield’s Sustainable Fuels Innovation Centre (SAF-IC) are pioneering synthetic alternatives to jet fuel. Researcher Ihab Ahmed, using a jet engine turned into a testbed, is testing sustainable aviation fuels (SAF) made from renewable sources like waste cooking oil, vegetable fats, agricultural waste, and even captured carbon dioxide.
SAFs offer environmental advantages by recycling carbon emissions rather than adding long-stored carbon into the atmosphere, as with fossil fuels. This reduces particulates and contrails, which harm health and contribute to climate issues. However, SAFs are not entirely carbon neutral due to emissions during production and transportation.
A Growing Demand for Change
As global air travel demand grows—spurred by expanding middle classes in countries like India and China—the aviation industry faces mounting pressure to find alternatives to fossil fuels. By 2050, airlines aim to achieve net-zero emissions, supported by advancements in aircraft efficiency. However, sustainable solutions such as hydrogen-powered or electric planes remain years away due to technical challenges like storage and energy density.
SAF: A Ready Solution
Unlike emerging technologies, SAFs are compatible with existing aircraft. Although current regulations limit airlines to using a blend with no more than 50% SAF, modern aircraft can burn 100% SAF. In a notable test, Virgin Atlantic flew a Boeing 787 from London to New York using fuel derived from waste fats and sugars.
Despite their potential, SAFs face hurdles. Production is minimal, making up just 0.05% of EU jet fuel, and costs remain high—three to five times more than traditional fuel. Governments are stepping in: the UK mandates that 2% of jet fuel must be SAF by 2025, increasing to 10% by 2030, while the EU aims for 63% by 2050.
Challenges to Scale
To meet demand, SAF production must scale up significantly. Feedstocks like biomass or human waste show promise but raise concerns about environmental impacts and competition with food production. Alternatively, “power to liquid” technology could create fuel using renewable electricity and carbon capture, but both methods are costly and energy-intensive.
Industry and Environmental Concerns
While the aviation industry pushes for increased production and lower costs, environmentalists remain skeptical. Critics argue that the sector continues to invest in fossil-fuel-reliant planes, undermining sustainability goals.
Investments in SAF
Despite challenges, progress is being made. At the Farnborough Airshow, Airbus, AirFrance-KLM, and others pledged $200m to fund SAF projects, while Boeing partnered with Firefly to develop SAF from human waste.
As the industry grapples with these issues, the future of SAF depends on technological advancements, policy support, and global collaboration to make sustainable aviation a reality.
