AMERICANS FOR CLEAN AVIATION FUELS

Clean aviation fuels (CAFs) provide an environmentally sound alternative to using conventional fossil-based jet fuel by significantly reducing lifecycle greenhouse gas (GHG) emissions. CAFs encompass the universe of sustainable aviation fuels (SAF), which are biofuels or synthetic fuels derived from renewable biomass feedstocks, waste resources, and renewable energy resources as well as captured carbon and hydrogen. Within this context, ACAF is focused on the benefits associated with the use of bio-based feedstocks derived from America’s heartland.

Building a market for CAFs has benefits that reach far beyond their environmental footprint. They can become the fuel that helps power America’s economic engine by creating good-paying jobs in the agricultural, feedstock production, energy generation, construction and manufacturing sectors, particularly as the on-road fuel market increasingly turns to electrification. In a recent report from the Air Transport Action Group, it is estimated that up to 14 million jobs globally could be created or sustained by the shift to SAF alone. Of those, 1.4 million jobs would be created in the production facilities themselves, while 12.6 million jobs would be created in the construction of those facilities, collecting feedstocks and the supply chain.

Harnessing the economic power of clean aviation fuels in the U.S. is not only a certain job creator, but by using these renewable resources from American farmers and energy producers to scale CAFs, we will reduce U.S. reliance on foreign energy sources and increase our global industrial competitiveness. 

Sustainable Aviation Fuel (SAF)

Today, SAF is the best decarbonization lever the aviation industry has in the near- to mid-term on its journey to net zero. SAF is a renewable biofuel or synthetic fuel used to power aircraft that has similar properties to conventional jet fuel but with a much smaller lifecycle greenhouse gas (GHG) footprint. In fact, SAF has the ability to reduce lifecycle GHG emissions by up to 80%, while some emerging SAF pathways even have a net-negative GHG footprint. While SAF still produces the same amount of GHG emissions from combustion as conventional jet fuel, lifecycle emissions reductions are achieved through the use of renewable feedstocks, sustainable agriculture practices, and other practices in the production and transportation of the fuel.

SAF can be produced via both biomass-based feedstocks, such as a variety of existing agricultural resources like waste wood and energy crops, oil seeds, agricultural residues, and wet wastes as well as non-biomass-based feedstocks. SAF produced from non-biomass based feedstocks is referred to as power to liquids (PtL) or e-fuels because renewable electricity serves as the primary source of energy coupled with the use of water electrolysis to produce green hydrogen paired with captured carbon dioxide. They undergo a series of conversion processes to become a liquid hydrocarbon that is the equivalent of jet fuel. However, e-fuels are currently in the early technology stages but have the potential to accelerate as the U.S. hydrogen and renewable energy industries scale.

SAF is considered a “drop-in” fuel because it can be used in current aircraft and engines. Much of the existing infrastructure in the U.S. is already equipped to transport large volumes of SAF, such as the Colonial Pipeline. Currently, neat SAF must be blended up to 50 percent with fossil derived jet fuel but efforts are underway to allow for 100 percent neat SAF utilization.

The aviation industry is gearing up for the SAF transition and airlines globally have committed to purchasing billions of gallons of SAF over the next few decades – signaling clear and reliable demand within the industry. However, there’s a problem; there isn’t enough SAF currently being produced to fuel the global aviation industry for a single day and it is not cost competitive. U.S. airlines have made ambitious commitments when it comes to the use of SAF, including a near-term target of achieving the availability of 3 billion gallons of cost-competitive SAF in the U.S. by 2030, which puts the aviation industry on a pathway to fully transition to SAF use by 2050.

• Alternative Jet Fuel (AJF): Currently, the majority of US SAF production and consumption occurs in the state of California, where SAF is referred to as alternative jet fuel (AJF).

Clean Hydrogen Fuel

Hydrogen is a potentially clean fuel that, if produced through zero carbon sources, and consumed in a fuel cell, produces only water. Hydrogen is a high-potential technology because of its critical role as a feedstock for SAF, and potentially as a direct energy source in aircraft. While the specific energy-per-unit mass of hydrogen is three times higher than traditional jet fuel, the tanks required to store it are multiple times heavier; and the resulting weight advantage or disadvantage is an area of research. Currently, hydrogen is primarily produced from natural gas or coal but can be produced from a variety of low- to no-carbon domestic resources such as nuclear, biomass, and renewable energy like solar and wind. Hydrogen has been safely used as a feedstock in the aerospace industry for decades – as an input into traditional jet fuel refining – but today the aviation industry is challenged to take this resource and adapt it more directly to commercial aviation’s energy needs. Specifically, the future of hydrogen aircraft could come in the form of hydrogen propulsion (e.g., hydrogen powered fuel cells, hydrogen-based jet engines, or a hybrid of hydrogen turbines and fuel cells), which would require extensively redesigning aircraft. It would also require an update the nation’s infrastructure delivery system. Synthetic fuels however; (described above) can be used in current aircraft engines, no modifications needed.