Tuesday, September 27, 2022

Plant-based jet fuel could reduce carbon emissions by nearly 70%

Currently, the global aviation industry produces around 2-3% of all human-induced carbon dioxide (CO2) emissions and is responsible for 3.5% of global warming. In order to reduce the carbon footprint of the aviation sector, researchers around the world are increasingly looking for sustainable alternatives to traditional aircraft fuel.

One of the latest alternatives comes from University of Georgia researchers. The team has developed sustainable aviation fuel (SAF) from a type of mustard plant that can replace petroleum-based aviation fuel and reduce carbon emissions by up to 68%.

The team, led by University of Georgia scientist Puneet Dwivedi, estimated the break-even price and life cycle carbon emissions of sustainable aviation fuel (SAF) derived from oil obtained from Brassica Carinata, a non-edible oilseed crop.

The latest growing number of SAF studies are aimed at providing a less demanding alternative to aviation fuel. For example, Rolls Royce conducted its first tests of 100% sustainable aviation fuel in a business jet engine earlier this year. Then, there are other alternatives such as liquid hydrogen and ammonia fuel; researchers also developed technology to convert waste plastics into jet fuel ingredients.

A blooming field of carinata.
A blooming field of Carinata. Credit: Bill Anderson

The new aviation fuel study comes after U.S. President Joe Biden proposed a sustainable fuel tax credit as part of the Sustainable Aviation Fuel Grand Challenge, which brings federal agencies together to scale up the production of SAF nationwide. With his new proposal, Biden set the goal of a 20% drop in aviation emissions by 2030 and achieving a fully zero-carbon aviation sector by 2050. The proposed tax credit requires a 50% reduction in life cycle carbon emissions, which the University of Georgia’s aviation fuel exceeds.

In addition, the price for producing Carinata-based SAF ranges from $0.12 per liter on the low end to $1.28 per liter, which is lower than the petroleum-based aviation fuel of $0.50 per liter when current economic incentives are included in the analysis. Carinata can also be grown in the ‘off’ season, which means it does not trigger food versus fuel issues. Additionally, according to Puneet Dwivedi, growing Carinata provides all the cover-crop benefits related to water quality, soil health, biodiversity, and pollination. His current research focuses on modeling the economic and environmental feasibility of producing and consuming Carinata-based SAF across Georgia, Alabama, and Florida by taking a supply-chain perspective.

“Our results would be especially relevant to the state of Georgia, which is the sixth-largest consumer of conventional aviation fuel in the country, hosts the busiest airport in the world, and is home to Delta, a leading global airline company,” Dwivedi said. “I am looking forward to pursuing more research for providing a sustainable alternative to our current model of air travel. Carinata has the potential to be a win-win situation for our rural areas, the aviation industry, and most importantly, climate change.”

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