How Aether Fuels' "radically simplified" process could solve SAF's biggest problems
By eliminating feedstock constraints and boosting efficiency, the Chicago startup aims to transform clean fuel production.
Scaling sustainable aviation fuel (SAF) has long been constrained by high costs, limited feedstock availability and yield inefficiencies. Aether Fuels wants to change that.
The Chicago-based startup — backed by Chevron, Eni, and Petronas — is developing “Aurora,” a new technology CEO Conor Madigan calls a “radically simplified evolution” of the Fischer-Tropsch process. It’s designed to make SAF more affordable by reducing production costs, expanding feedstock options, and increasing fuel output.
The company expects to initially supply SAF "in similar ranges as HEFA products today" but without feedstock constraints, then achieve its $1,600 per tonne target through plant optimisation over time.
Aether Aurora cuts complexity, boosts efficiency
Aether's platform can convert any waste carbon stream — from captured CO2 and industrial waste gases to municipal solid waste and agricultural residues — without requiring equipment modifications.
"We can take in any combination of CO, CO2, light hydrocarbons and hydrogen," Madigan explains. "What that means is we can go build plants now using biogas or industrial waste gas, but we can also build e-fuel plants when and if CO2 and hydrogen reach the right cost structure."
The company claims 95% carbon conversion efficiency, significantly higher than direct CO2 hydrogenation competitors, while achieving what it rates as "excellent" capital efficiency compared to conventional Fischer-Tropsch technology.
Central to the breakthrough are three proprietary innovations:
An electrified syngas generation system that eliminates the need to burn feedstock for process heat.
A "tri-converter" reactor that replaces 2-3 conventional reactors.
And an upgrading system that processes raw Fischer-Tropsch products without costly intermediate separations.
Strategic partnerships validate tech and unlock scale
Madigan says that the backing from three major oil companies provides both validation and global scaling capabilities. "These are companies whose whole business is building large plants all over the world and understanding how to do that successfully with new technology," Madigan noted.
Beyond financial investment, Aether has secured memoranda of understanding with JetBlue and Singapore Airlines. Both carriers are now in "active discussions" for firm offtake agreements. JetBlue is also an investor in the company.
The partnerships reflect growing airline urgency around SAF supply security, and Madigan was confident about securing bankable offtakes. "Everybody knows that if you can make the SAF, people will buy the SAF," Madigan observes, highlighting seller's market dynamics driving aviation fuel procurement strategies.
Aggressive timeline targets 2028 operations
Aether plans to announce its first small commercial plant location later this year, targeting a 50-barrel-per-day demonstration facility to be operational by 2028, followed by a full-scale 1,000-2,000-barrel-per-day plant by 2031.
The company expects to complete Series B funding next year and Series C financing after the demonstration plant begins operations, with project-level equity partnerships for larger facilities. Key backing comes from the Xora fund, which is part of Temasek Holdings.
"We try to be pretty conservative and not make unreasonable projections," Madigan says regarding cost targets. "When we go and build our first plants, we expect that we can supply product in similar ranges as HEFA products today, but without the feedstock constraints."
Emerging demand from maritime could disrupt SAF supply dynamics
However, Aether's technology flexibility comes with a strategic warning for aviation executives. The same feedstocks and production capabilities that serve aviation can also produce sustainable marine diesel. Madigan anticipates that the International Maritime Organisation's (IMO) greenhouse gas reduction rules could create a market "even bigger than the SAF market."
"In one stroke of the pen, their market is going to become even bigger than the SAF market," he predicted, referencing proposed IMO regulations. "The same feedstocks that are being used to make SAF are being used to make marine fuels."
This potential competition for sustainable fuel production capacity could force airlines to accelerate procurement strategies and accept longer-term commitments to secure supply, particularly as maritime operators transition from cheaper alternatives like FAME (fatty acid methyl esters) to premium sustainable fuels.
Implications for aviation
For the industry, all this represents both opportunity and urgency. The technology can potentially address persistent SAF supply constraints while offering cost advantages. Still, the maritime competitive threat suggests that the current window for securing favourable long-term agreements and consistent supply may narrow.
The company's waste-only feedstock strategy also aligns with sustainability requirements, avoiding food-versus-fuel concerns while maintaining compliance with EU renewable energy directive requirements for at least 65% greenhouse gas reduction.
As the SAF industry approaches critical scaling inflexion points, technologies like Aether Aurora that combine feedstock flexibility with cost competitiveness will become more crucial in helping airlines secure reliable, affordable, sustainable fuel supplies for their net-zero commitments.
Aether Fuels operates R&D facilities in Chicago with strategic partner GTI Energy and is establishing a second headquarters in Singapore.