United Airlines Inc. via its recently formed United Airlines Ventures, and Honeywell International Inc (Honeywell), a global industrial technology, processes, and performance materials major, have announced a joint multimillion-dollar investment in US-based cleantech developer Alder Fuels LLC. United Airlines has also agreed to a 1.5 billion (US) gallons (≈ 5.68 billion litres) SAF offtake from Alder Fuels, the world's largest publically announced SAF offtake agreement.
Please reload the page
Do you want to read the whole article?
- Six editions per year
- Full access to all digital content
- The E-magazine Bioenergy international
- And more ...

Alder Fuels is pioneering first-of-its-kind technologies for producing sustainable aviation fuel (SAF) at scale by converting abundant biomass, such as forest and crop waste, into sustainable low-carbon, drop-in replacement biocrude oil that can be used to produce aviation fuel.
When used together across the fuel lifecycle, the Alder technologies, coupled with Honeywell’s “Ecofining” process, could have the ability to produce a carbon-negative fuel at spec with today’s jet fuel. The goal of the technologies is to produce fuel that is a 100 percent drop-in replacement for petroleum jet fuel.
As a pioneer of the SAF market with UOP Ecofining technology, our work with United and Alder on this new technology will help transform the industry and support the growth of a zero-carbon economy. This solution will not only advance United’s SAF commitment but can help the aviation industry meet its commitments to decouple increases in carbon emissions from growth in passengers, said Darius Adamczyk, Honeywell Chairman, and CEO.
United behind world’s largest offtake agreements
As part of the agreement, United Airlines is committing to purchase 1.5 billion (US) gallons (≈ 5.68 billion litres) of SAF from Alder when produced to United’s requirements. United’s purchase agreement, which is estimated to be one and a half times the size of the known purchase commitments of all global airlines combined, makes this the largest publicly announced SAF agreement in aviation history.
United’s purchase agreement with Alder also surpasses the previous record set by the airline in 2015 through its investment in Fulcrum BioEnergy with its option to purchase up to 900 million gallons (≈ 3.4 billion litres) of SAF.
Since announcing our 100 percent green commitment in 2020, United has stayed focused on decarbonizing without relying on the use of traditional carbon offsets. Part of that commitment means increasing SAF usage and availability since it’s the fastest way to reduce emissions across our fleet. However, to scale SAF as quickly as necessary, we need to look beyond existing solutions and invest in research and development for new pathways like the one Alder is developing. United has come further than any other airline making sustainable travel a reality by using SAF to power flights. Our leadership gives customers confidence that they are flying with an airline that recognizes the responsibility we have to help solve climate change, said United CEO Scott Kirby.
Utilize available forestry- and agricultural residues
According to the US Department of Energy (DOE), forestry residues and agricultural residues in the United States alone could provide enough biomass energy to generate more than 17 billion gallons (≈ 64.3 billion litres) of jet fuel and displace 75 percent of US aviation fuel consumption.
If the country were to broadly adopt regenerative agricultural practices, which capture more carbon in healthier soil compared to traditional methods, it could generate an additional seven billion gallons (≈ 26.5 billion litres) of SAF, which would completely replace the country’s current fossil jet fuel consumption.
Alder’s technology and demand for its fuel from the aviation industry create a large new market for biomass from regenerative practices. The use of this biomass further enables Alder’s production process to be carbon negative over the fuel’s lifecycle.
Aviation poses one of the greatest technology challenges for addressing climate change and SAF has demonstrated the greatest potential. However, there is insufficient raw material to meet demand. Alder’s technology revolutionizes SAF production by enabling use of widely available, low-cost and low-carbon feedstock. The industry is now a major step closer to using 100 percent SAF with our drop-in fuel that accelerates the global transition to a zero-carbon economy, said Bryan Sherbacow, CEO of Alder Fuels and Senior Advisor to World Energy LLC, the company that owns and operates the world’s first SAF refinery.
A trio of SAF pioneers
Prior to founding Alder, Sherbacow built the world’s first SAF refinery utilizing Honeywell’s technology and subsequently contracted with United, enabling the airline to become the first globally to use SAF in regular operations on a continuous basis.
Since then, United has purchased more SAF than any other airline and, with this agreement now, has more than 70 percent of the airline industry’s publicly announced SAF commitments. Alder’s research is supported by the US Defense Logistics Agency, the DOE, and a partnership with DOE’s National Renewable Energy Laboratory (NREL), focused on developing technology to process organic waste and sustainable, non-food plant material into carbon-negative transportation fuels.
Honeywell innovation established the SAF market with its UOP Ecofining process, the first technology used to maximize SAF production for commercial aviation. Building on the company’s focus to create sustainable technology, Honeywell will utilize its expertise and proven process of developing sustainable fuels alongside Alder, applying proprietary hydroprocessing design to the process to jointly commercialize the technology.
Commercialization is expected by 2025, and according to Honeywell, is a clear example of how Honeywell’s Sustainable Technology Solutions business can partner with early-stage companies and help them scale faster, access customers, and advance research and development to help drive sustainability at the global level.