A partnership between the Pacific Northwest National Laboratory (PNNL), biorefining firm Green Plains (NASDAQ:GPRE) and energy infrastructure provider Tallgrass has been awarded funding by the US Department of Energy (DoE) with the aim of advancing its sustainable aviation fuel (SAF) technology.
- PNNL, Green Plains and Tallgrass have secured DoE funding to optimise, pilot and commercialise PNNL’s SAF technology.
- The investment signals confidence that PNNL’s solution can overcome the challenges of producing SAF at a commercial scale.
- Although scaling and commercialising SAF is an important step, the aviation industry faces many ongoing sustainability issues that remain unaddressed.
The Pacific Northwest National Laboratory (PNNL) has developed a novel process for converting ethanol into sustainable aviation fuel (SAF), and has given Green Plains and Tallgrass the option of licensing its technology.
With the DoE’s backing, which comes as part of the federal agency’s drive to support the development of valuable biofuels and bioproducts, the partners plan to demonstrate PNNL’s technology through a pilot project producing SAF from ethanol via the ASTM-approved alcohol-to-jet (AtJ) pathway.
Successful completion of the project is expected to enable the technology to be commercialised at scale.
Tallgrass president and CEO Matt Sheehy said, “we believe it is critical to develop and invest in the infrastructure to produce and transport the next generation of clean fuels. We are excited to work alongside Green Plains and PNNL to advance this pioneering SAF production technology and the infrastructure to commercialize large-scale SAF production.”
The role of SAF in decarbonising aviation
The airline industry is estimated to account for around 2.5% of global greenhouse gas emissions, highlighting the urgency of addressing its significant environmental impact.
Global air travel is expected to increase, however, with its fuel consumption projected to rise from 100 billion gallons per year to around 230 billion gallons by 2025.
Under pressure to accommodate this growth sustainably, airlines across the globe have pledged their commitment to carbon neutral growth from 2021 onwards. US airlines have set a more specific target of halving their CO2 emissions by 2050, as compared against 2005 levels.
Unfortunately, the options available for decarbonising aviation are fairly limited. The vast majority of airplanes are too large and heavy to be powered by batteries, and there isn’t much more the sector can do to lower equipment and operational efficiencies beyond what has already been achieved.
The term SAF applies to liquid fuels that emit less CO2 than conventional fossil fuel-based jet fuel. These fuels can be produced in a variety of ways, using biologically derived feedstocks, waste streams, or via synthetic approaches involving carbon capture.
Such fuels are currently in use by more than 50 airlines and had powered more than 450,000 commercial flights as of April 2022. The volume of SAF needed to take on its role in decarbonising aviation, however, will require a major increase in production.
This will be a significant challenge, as the development of SAF still has many challenges to overcome. Ongoing issues include cost, decarbonisation potential, useability as a “neat” fuel rather than a blend with conventional kerosene, and other complexities in both supply chain and technological capabilities.
How will the PNNL, Green Plains and Tallgrass overcome these challenges?
The DoE’s investment in PNNL’s technology indicates its confidence that the solution will succeed where others might struggle. SG Voice contacted Todd Becker, CEO and president of Green Plains, to find out how the partners differentiate themselves from the rest of the market.
Becker explained how the project’s potential lay in combining each partner’s strengths.
PNNL’s technology streamlines the AtJ process, removing one of the main steps normally required, and involves exothermic reactions that lower its energy input requirements. Green Plains offers an abundant supply of ethanol in addition to its advanced catalyst optimisation technology, while Tallgrass will provide access to its sizeable infrastructure network.
Further support comes from the recent introduction of the US Inflation Reduction Act (IRA), which Becker says has been crucial in enabling the economic feasibility of SAF production.
Regarding supply chain concerns, Becker confirmed that the ethanol will be made with domestically grown, locally sourced corn.
Although US ethanol production exceeds the volume needed to accommodate Becker’s projected 3 billion gallon per year SAF demand, he said there will likely be competition against those who seek its use for motor fuels.
Becker dismisses concerns around changes in land use as, “an old story”, claiming there is no evidence to suggest an expansion of acreage. Whether this is truly the case or not, he admits that corn farms contribute around 28 carbon intensity points to the supply chain that could be improved but not fully eliminated.
Green Plains plans to reduce its carbon intensity in numerous ways, including an upcoming carbon capture agreement with Summit Carbon. The IRA, he says, provides the basis for making decarbonisation efforts more attractive to the firm’s stakeholders.
Ultimately, Becker concludes that, “the key is, it has to happen”.
He believes there will not be a single winner in terms of specific technologies used, but that the AtJ pathway, primarily relying on US ethanol, is the only viable method for producing SAF at the scale required.
It’s not all about the fuel
Although the ideal of scalable, economically viable and technically advanced SAF is a clear step forward in the aviation industry’s route to sustainability, innovative fuel alternatives will not solve all of the sector’s problems.
From airplane manufacturing to the resource consumption of ground operations, every component of the sector’s value chain has some impact on the planet. Once in flight, carbon emissions are responsible for just a third of an airplane’s total climate impact, with nitrous oxide emissions and contrails contributing a far greater share of 67% combined.
