PULLMAN, Wash. — The United States could feasibly produce enough sustainable aviation fuel to meet roughly two-thirds of its 2030 federal target, but getting there will require overcoming major hurdles, according to a new Washington State University-led study.
Published in the March edition of Biomass and Bioenergy, the study offers one of the most detailed looks yet at the nation’s sustainable aviation fuel, or SAF, industry. The work is part of a broader body of research at WSU that has helped position the university as one of the leading research institutions studying sustainable aviation fuel.
The researchers found that while domestic production is expanding quickly, the United States remains unlikely to meet its goal of producing 3 billion gallons of sustainable aviation fuel annually by 2030 without additional support and continued industry investment.
The study found that the most optimistic scenario projects domestic SAF production could reach about 2.1 billion gallons annually by 2030, roughly two-thirds of the federal target, though substantially lower production levels may be realized depending on market conditions, project delays and policy support.
“We wanted to take a very pragmatic look at where we really are,” said Kristin Brandt, an adjoint faculty member in the Composite and Materials and Engineering Center in WSU’s Voiland College of Engineering and Architecture and lead author on the study. “There are people saying this industry is going to explode overnight and others saying nothing will happen at all. The reality is somewhere in between.”
Sustainable aviation fuel has emerged as one of the aviation industry’s leading near-term strategies for reducing carbon emissions because it can already be blended with conventional jet fuel and used in existing aircraft and airport infrastructure.
There are people saying this industry is going to explode overnight and others saying nothing will happen at all. The reality is somewhere in between.
Kristin Brandt, adjoint faculty member
Voiland College of Engineering and Architecture
Washington State University
Depending on how it is produced, SAF can reduce lifecycle greenhouse gas emissions by roughly 80% compared to traditional petroleum jet fuel. Current fuels are commonly made from renewable or waste-based lipids such as used cooking oil, animal fats and vegetable oils like soybean oil.
Brandt’s study analyzed publicly announced U.S. renewable fuel projects stretching back more than two decades. The team examined how often announced projects actually become operational, how long facilities take to build and whether enough feedstock exists to support projected growth. Researchers also analyzed whether producers are financially incentivized to make aviation fuel instead of renewable diesel for cars and trucks, which is often more profitable under current U.S. policies and market conditions.
One of the study’s major findings is what researchers describe as the gap between announcements and reality.
“Announcements are not the same thing as fuel,” Brandt said. “People announce giant facilities with aggressive timelines all the time, but historically many projects get delayed, scaled back or never move forward.”
To better estimate likely production, the researchers developed what they call an “implementation ratio,” a way of estimating how many announced facilities will ultimately succeed. Historically, only about half of announced projects become operational, though mature technologies tend to perform better.
The study also found that hydroprocessed esters and fatty acids, known as HEFA, will likely dominate U.S. SAF production through 2030. These fuels are largely made from fats, oils and greases such as used cooking oil and animal fats.
“There’s actually a global shortage of used cooking oil,” Brandt said. “It sounds ridiculous, but it’s true.”
The paper reflects a wider range of SAF research underway across WSU.
A recent bibliometric analysis published in the journal Heliyon identified WSU as the top contributing institution globally in sustainable aviation fuel scientific literature from 2001–23. WSU researchers Joshua Heyne, Michael Wolcott, Manuel Garcia-Perez and Brandt were all identified among the field’s most influential researchers.
Much of that work is connected to ASCENT, the FAA Center of Excellence for Alternative Jet Fuels and Environment, which is co-led by WSU and MIT. Wolcott, Regents Professor and director of ASCENT and a co-author on the new study, said the university’s strength comes from bringing together researchers working across chemistry, engineering, economics, supply chains and policy.
“Bringing about societal changes in energy systems are enormous transitions,” Wolcott said. “It will take years and multiple disciplines to realize progress.”
The study also highlights why sustainable aviation fuel is expected to remain one of the aviation industry’s most practical tools for reducing emissions in the coming decades. Commercial aircraft often remain in service for decades, and replacing the fueling infrastructure that supports global air travel would take enormous time and investment.
“When you think about aviation globally, these airplanes fly everywhere,” Brandt said. “Even if policies differ between countries, airlines operating internationally are still going to have to meet global standards. This is something the industry is going to have to work through together.”
For the researchers, the goal was not to discourage the industry but to provide a clearer picture of the challenges ahead as aviation works toward a lower-carbon future.
“If we want to hit these goals,” Brandt said, “we need to be honest about the barriers and realistic about what it will take to overcome them.”
Media Contacts
- Michael Wolcott, Regents Professor, Department of Civil and Environmental Engineering, 509-335-6392, wolcott@wsu.edu
- Will Ferguson, WSU News & Media Relations, 509-335-8798, will.ferguson@wsu.edu
- Kristin Brandt, WSU Composite Materials & Engineering Center, kristin.brandt@wsu.edu
