Carbon dioxide (CO2) from US ethanol plants could soon help power aircraft, according to new research from scientists at the University of Michigan (UMich) in Ann Arbor, Michigan.

The UMich team found that CO2 released during ethanol fermentation – around 85% of total production emissions – is highly pure and easier to capture than emissions from coal or cement plants. As the corn used to produce ethanol already absorbs atmospheric CO2, recycling this gas into jet fuel would reuse existing carbon rather than add more to the atmosphere.

Study lead author Stephen McCord said the approach turns a by-product into a “significant asset,” offering a new route to decarbonise aviation, which currently produces more than a gigatonne of CO2 annually.

In 2023, US ethanol production emitted roughly 48 megatonnes of CO2, representing a vast untapped source for sustainable aviation fuel.

The study compared pathways for converting ethanol or captured CO2 into jet fuel. The conventional “Alcohol-to-Jet” method cuts carbon intensity up to 20%, whereas two CO2-based alternatives, the gas fermentation route and Fischer-Tropsch synthesis, achieved reductions of up to 84% and 90%, respectively.

With electrification and hydrogen still limited for long-haul flights, such low-carbon fuels could provide a realistic, near-term path to “defossilize” aviation and make substantial progress towards net-zero flight.

Image Credit: Source