January 27, 2022 • 3 min read
How can sustainable aviation fuel decarbonize air travel?
Aviation fuel usually comes from crude oil, but sustainable aviation fuel is becoming more viable, and it will play a key role in decarbonizing the aviation industry.
Apart from 2020, can you remember a time when you looked up and didn’t see planes in the sky? Air travel has become an indispensable part of modern life. We depend on aircraft to take people on holiday, to see family abroad, to build businesses, and to transport products, food, and post all over the world.
The aviation industry made destinations that used to take days, weeks, or even months to visit, accessible within hours. That’s why tens of millions of people board airplanes every year, and millions more will take to the skies over the coming decades.
However, air travel has reached a critical juncture, as CO2 emissions from human activity heat our planet. We need to find a pathway to carbon-neutral aviation. But how?
The problem with traditional aviation fuel
Air travel is responsible for approximately 2.8 percent of global CO2 attributable to fossil fuels (IEA). Most of this CO2 is emitted when the fossil-fuel-derived jet fuel is combusted in jet engines.
The aviation industry is committed to net-zero carbon emissions by 2050. This target will require a combination of low-carbon fuels, new propulsion technologies, infrastructure upgrades, efficiency improvements, carbon capture, and carbon offsetting schemes.
But with jet fuel emissions growing, commercial aviation needs an immediate decarbonization solution. And the only viable low-carbon replacement for fossil-fuel jet fuel is sustainable aviation fuel.
What is sustainable aviation fuel?
Sustainable aviation fuel, commonly referred to as SAF, is an environmentally sustainable alternative to fossil-fuel jet fuel. It must have identical or superior performance to traditional jet fuel, but there’s a big difference; we do not need crude oil to produce it. Producers make this green aircraft fuel from a variety of sources including used vegetable oils, household waste, waste gases, animal fats, forestry residue, and even CO2 captured directly from the air.
SAF is referred to as a drop-in fuel because it can replace fossil-fuel airplane fuel. You don’t need to make any modifications to the aircraft’s engine or fuelling system to use SAF, and you can also use existing infrastructure to transport, store and distribute it at airports.
Why is sustainable aviation fuel important?
SAF reduces the carbon intensity of air travel by up to 80 percent over its life cycle (IATA). That makes SAF the most viable option to decarbonize the aviation sector with the technology we’re already using today.
SAF has helped to power over 370,000 flights since 2016, and global production totaled 100 million liters in 2021 (IATA). However, SAF makes up only one percent of all jet fuel produced today. To meet the industry’s net zero targets, SAF needs to be the primary fuel source by 2050. This requires the production capacity of SAF to increase over 50 times compared to current production levels.
How is sustainable aviation fuel made?
There are six certified pathways to produce SAF. These include Fischer-Tropsch, hydrotreated esters and fatty acids (HEFA), alcohol-to-jet, and other less-developed processes.
These processes vary in technical and commercial aspects, but they each produce a liquid fuel that can replace fossil-fuel-derived jet fuel.
We generate waste all over the world, so the feedstocks for SAF can come from anywhere, rather than just oil-rich nations. This could change the dynamics of the aviation industry because if waste feedstocks are readily available, more countries can build the processing facilities, refineries, and infrastructure to produce SAF and supply a clean substitute for fossil jet fuels to the world.
The flight path to carbon-neutral aviation
By 2050, SAF will contribute to the abatement of over 50 percent of CO2 emissions associated with the aviation industry (IATA). Right now, SAF production is increasing yearly, helping the aviation industry meet its decarbonization targets and abide by existing and upcoming legislation.
In addition to SAF, other solutions such as battery and hydrogen fuel cells powered aircraft will have to be implemented and fully commercialized. And this will require government and industry collaboration. Only then will we achieve the ambition of a carbon-neutral aviation industry.