For every fraction of a degree the Earth warms, people are experiencing exponential effects. Increasingly extreme, unpredictable weather patterns create a cascade of systemic effects on our environment, economies, food security, human health, population migration and more.

The world’s decision to limit the rise in average global temperature by 1.5°C is both ambitious and vital. This commitment has spurred innovation and incentives across industries and is resulting in substantial positive change to emissions in many industrialized countries.

Demand for fossil fuels remains high because energy is a necessity — and appetite for it is only expected to grow. If the U.S. is going to meet its climate neutrality goals for 2050, it needs to expand its commitment to producing more renewable, clean sources of energy, delivered in ways that are practical, affordable and scalable. That means speeding up transformation across sectors, with a focus on those areas where energy conversion can make the biggest impact, such as transportation.

Reducing emissions and increasing renewables

In the U.S., transportation accounts for 28.4% of carbon emissions — the largest share of any sector. Renewable diesel has been a game-changer for reducing carbon intensity on America’s roadways. The next frontier will be the skies. Sustainable aviation fuel offers particular promise both ecologically and economically, including fostering job creation in both rural and urban areas, because of rapidly growing demand.²

The world used about 100 billion gallons of aviation fuel in 2024,³ and demand is expected to rise by more than 50% by 2050.⁴ If the industry can supply more of this fuel with renewables, it would be a huge step forward. Getting there requires maximizing production of sustainable aviation fuel by leading in processes that offer the greatest opportunities for returns.

Pathways to progress with sustainable aviation fuel (SAF)

Sustainable aviation fuel (SAF) is produced from agricultural, forestry, and other waste feedstocks, making it less carbon intensive than traditional jet fuel. SAF can be blended with petroleum jet fuel, and it’s replacing an increasing percentage of what’s in the tank. SAF is immediately viable, and adoption is growing rapidly, offsetting fossil fuel use in aviation. By 2035, SAF is expected to displace 11% of worldwide jet fuel demand — which will require delivering around 13 billion gallons of SAF annually.⁵ To meet that demand, the world will need to produce over 25 times more SAF in the next decade than was produced in 2024.⁶

SAF production is further driven by substantial incentives from local, state and federal governments, including the Clean Fuel Production Tax Credit for transportation fuel production, which is currently set to run through 2027.⁷ SAF production is also forecast to add thousands of jobs to the U.S. economy annually, in diverse roles from engineering to agriculture.⁸

SAF is produced through four major pathways, each of which relies on different types of feedstocks.

• HEFA stands for hydrotreated esters and fatty acids. This process uses vegetable oils, waste oils and fats and is the approach used to deliver SAF to the market over the last decade. However, limited feedstock will cap how much SAF can be produced from this process.
• Methanol to jet (MTJ) uses methanol as a marketable, transportable, intermediate for jet fuel production. When the methanol is derived from organic waste sources like biomass, biogas or municipal solid waste (MSW), it can be further refined into SAF. Alternatively, a combination of green hydrogen and captured carbon dioxide can be used to synthesize electro-methanol, which can be upgraded to electro-SAF (eSAF).
• Fischer-Tropsch is the first ASTM-approved pathway for producing SAF. It uses waste biomass, biogas, MSW, or green hydrogen combined with carbon dioxide to produce liquids and waxes which are then further refined for use as SAF or eSAF.
• Ethanol to jet (ETJ) leverages ethanol derived from grain, corn, sugarcane or other ethanol-producing plants that are plentiful in the U.S., which is converted to SAF. There is also an opportunity to convert agricultural waste to SAF through the ETJ pathway.

U.S. market advantages for ethanol to jet

Honeywell UOP leads in innovation and productivity across all four SAF pathways to expand feedstock accessibility and give producers diverse options to meet the needs of their operations, customers and global climate compliance regulations. 

However, among these pathways, ethanol to jet is the second-most commercially viable option after HEFA.⁹ For U.S. refiners, producers and project developers, ethanol to jet offers a chance to diversify their business and introduce a new revenue stream by delivering this desired option to an expanding aviation market. The U.S. has substantial feedstock resources for ethanol to jet and the production process itself is cost effective and has a favorable carbon intensity score when combined with carbon capture and sustainable agriculture practices.⁵ All of this puts U.S. ethanol in an excellent position to supply the fast-expanding domestic and international markets for SAF.

Capitalizing on options and opportunities

It’s prime time for producers of SAF to recognize significant value from their fuels. Demand, tax incentives and the high availability of crop feedstocks make ethanol to jet one of the most appealing of these options for U.S. producers of SAF. With profitable models for production, ethanol to jet SAF will chart a path toward a 100% renewable aviation fuel future.

References:

¹ Environmental Protection Agency. (2024, June). Climate Change Indicators: U.S. Greenhouse Gas Emissions. https://www.epa.gov/climate-indicators/climate-change-indicators-us-greenhouse-gas-emissions

²Third Way. (2024, April 5). Soaring to New Heights: The Economic Impacts of Building an American SAF Industry.

https://www.thirdway.org/report/soaring-to-new-heights-the-economic-impacts-of-building-an-american-saf-industry

³ National Renewable Energy Laboratory. (2024, March). The Challenge Ahead: A Critical Perspective on Meeting U.S. Growth Targets for Sustainable Aviation Fuel. https://www.nrel.gov/docs/fy24osti/89327.pdf

⁴ S&P Global Commodity Insights. (2024, August 7). Infographic: Jet fuel demand soars as SAF takes flight. Commodity Insights Live. https://cilive.com/commodities/agriculture/news-and-insight/080724-infographic-jet-fuel-demand-soars-saf-flight-summer-travel-aviation-pandemic-kerosene-cargo-decarbonization

⁵ Boubin, M. (2024, October 14). The importance of U.S. ethanol engagement within a competitive global SAF Market. Ethanol Producer Magazine. https://ethanolproducer.com/articles/the-importance-of-us-ethanol-engagement-within-a-competitive-global-saf-market

⁶ International Air Transport Association (IATA). (2023, December 6). SAF Volumes Growing but Still Missing Opportunities. Retrieved from https://www.iata.org/en/pressroom/2023-releases/2023-12-06-02/.

⁷ Sabin Center for Climate Change Law, Columbia Law School. (2025, January 28). Ira section 13704 - clean fuel production credit. Inflation Reduction Act Tracker. https://iratracker.org/programs/ira-section-13704-clean-fuel-production-credit/

⁸ O’Rear, E. G., Jones, W., Bower, G., Adeyemo, M., King, B., & Pastorek, N. (2023, October 25). Sustainable Aviation Fuel Workforce Development: Opportunities by Occupation. Rhodium Group. https://rhg.com/research/sustainable-aviation-fuel-workforce-development/

⁹ Howe, C., Rolfes, E., O’Dell, K., McMurtry, B., Razdan, S., & Otwell, A. (2024, November). Pathways to Commercial Liftoff: Sustainable Aviation Fuel. U.S. Department of Energy. https://liftoff.energy.gov/wp-content/uploads/2024/12/LIFTOFF_-Sustainable-Aviation-Fuel_Updated-2.6.25.pdf