Resist the Siren Call of Aviation Biofuels


By Gary Graham Hughes, California Policy Monitor, Biofuelwatch

The climate damaging impacts of flying are becoming harder and harder to ignore and are increasingly of concern to a climate educated public.

Anticipating this shift in public opinion about flying and seeing their business plans of endless growth jeopardized, the aviation industry, with the assistance of elected officials and government agencies, has pivoted hard to promote aviation biofuels as a climate solution.

As far as for what those fuels would be made from, regardless of gestures made by producers towards used cooking oil or animal waste products, on a global level palm oil is by far the preferred vegetable oil feedstock for aviation biofuels, while in the USA the trend is irrefutably towards soy as the primary feedstock.

Because of commodity market elasticity and growing global demand, both commodities are linked both directly and indirectly to climate and biodiversity damaging land use change and deforestation.

Regardless of well documented concerns about the social injustice and climate unfriendliness of bioenergy, the concept of “Sustainable Aviation Fuels” (SAF) is now central to aviation industry plans to ostensibly ’decarbonize’ and address the impacts from the sector. Indicative of the momentum SAF is getting in decision making circles, prominent Democrats like US Senators Sheldon Whitehouse (Rhode Island) and Diane Feinstein (California), as well as their peers in the House of Representatives, have recently taken up the campaign for the aviation industry and have introduced legislation to subsidize and foment the expansion of the production of aviation biofuels under the green mantle of achieving the environmental sustainability of the highly polluting air transport sector.

The basic idea justifying biofuels as a climate solution is that it is theoretically possible to counterbalance the CO2 emitted during the combustion of biofuels in aircraft engines by the absorption of an equivalent quantity of CO2 by the plants used or planted afterwards, during their growth.

Regardless of the flaws in the assumption of ‘carbon neutrality’ embedded in bioenergy, the best contemporary science regarding aviation climate impacts shows that the full climate impact of jet flight is three times that of the warming from the CO2 emissions. This is due to the radiative forcing impact of the combustion of fuels, including biofuels, at high altitudes.

Ultimately, because of the failure to address in any way the full climate impact of burning fuel at high altitudes while turning a blind eye to the ramifications of burning food as fuel, the reasoning leading to present biofuels as a major solution to ‘decarbonize’ the aviation sector and thus reduce climate impact is erroneous and even misleading.

The industry celebrates “Sustainable Aviation Fuel” (SAF) as an innovative technological solution, but beyond the disputed climate benefits of aviation biofuels themselves is the fact that in the foreseeable future SAF would be at best a 50% mix with fossil based kerosene jet fuel.

Another fact that SAF proponents have not been forthcoming in sharing is that the hydrotreated vegetable oil refining process requires massive amounts of hydrogen, derived largely from fossil gas, resulting in very high greenhouse gas emissions from the refining process itself, equal to or possibly exceeding the emissions from the processing of petroleum based jet fuel.

In practical terms, SAF allows for long-term fossil fuel lock in, while concurrently expanding the use of climate damaging biofuels under the guise of responding to the global climate crisis.

What the proponents of SAF are not telling the public is that biofuel feedstock production and biofuel processing and manufacturing come with a well known list of environmental, climate, land use, public health, social justice and human rights issues, as well as a host of as yet still unknown risks and uncertainties.

Climate impacts related to land use change for bioenergy feedstock production include both Direct Emissions (expansion of industrial agriculture to meet increased market demand) and Indirect Emissions (the complete interactions of market elasticity, cross commodity market dynamics and the resulting expansion of industrial agriculture). Deforestation is one of several serious global environmental threats directly attributed to the expansion of industrial agriculture in response to increases in global demand for agricultural commodities for use in food, feed and fuel.

Halting deforestation is unquestionably among the highest priorities for global climate action. Promoting the expansion of the production and use of aviation biofuels is totally and completely counter productive when it comes to advancing a climate and biodiversity protection agenda that will be effective in addressing global deforestation.

The severe climate impacts from aviation are also crucial to understanding the promotion of biofuels in the context of economic equity, global climate justice and a Just Transition. Data shows that up to 50% of climate impacts from aviation come from the transportation habits of just 1% of the global population. Globally less than 20% of the worlds population ever actually flies, meaning that 80% of the world’s population are not responsible for the climate impacts of aviation, but they are having to deal with the resultant climate chaos all the same.

But even of those who do fly the most significant portion of the environmental impacts come from the flying habits and preferences of the super rich.

Industry narratives have led to public perception of air travel being a relatively small problem, which has lead to a lack of transparent discussion of the pollution of the industry and a failure to secure effective mitigation of the industry’s climate impact. Making the situation worse is the perpetuation by the industry and many other stakeholders of other false solutions such as carbon offsets, as well as technological unicorns such as electric or hydrogen powered flight, which are decades from being scalable, if ever.

These greenwashing tactics distract dangerously from the real tasks at hand.

The simple fact of the matter is that those few people who do have the privilege of flight must fly less, if we fly at all. The aviation industry objectives of endless growth will never be compatible with climate justice. Even if some few of the sector’s technological fantasies were to come to fruition such advances will not occur until long after the sands in the climate hourglass have already run out.

What we cannot avoid is that there is an imperative to reduce aviation dramatically and to greatly improve locally oriented and community supported ground and marine transportation.

We must resist the siren call of climate dead ends like aviation biofuels. Under scrutiny these supposed low carbon alternatives do not stand up to a necessary litmus test regarding climate benefits, and in particular there are far too many injustices and too much environmental damage embedded in the global expansion of the palm and soy monoculture models for such a pivot to be considered viable.

Not all that glitters is green, and few case studies exemplify this rule more than the efforts of the aviation industry to rebrand itself as a climate leader with their plans to expand the production and use of aviation biofuels.

To learn more about the climate impacts of aviation and the imperative of a Just Transition in the sector visit the website of the Stay Grounded network (