The Texas refinery that produces biofuel from cattle, contributing to deforestation

While electrification is being used to reduce the impact of polluting emissions in road transport, including cars and trucks, the situation in aviation is more complex. And batteries aren't part of this. Currently, both the United States and Europe are focusing on SAF , an acronym for Sustainable Aviation Fuel , a fuel produced from sustainable sources, such as vegetable oils, animal fats, agricultural waste , but also algae or captured carbon dioxide. SAF can reduce greenhouse gas emissions by up to 80 % over the life cycle of an aircraft running on traditional fuel. This reduction includes emissions from production, transportation, and fuel combustion. Unfortunately, even today, the percentages of SAF used in aviation are very low.

Globally, the United States is the world's largest producer. In 2023 , American SAF production is estimated to have reached 190 million liters, but this still represents less than 1% of the country's total jet fuel consumption. The global jet fuel market, though small, is expected to be worth approximately $2.9 billion in 2025 , according to analyst firm SkyQuest Technology Group, compared to the $239 billion global market for conventional aviation fuel.

Within this production chain, which despite its small numbers generates billions of dollars in revenue, lies a murky affair linking a Texas manufacturing company to the Amazon rainforest. This time, trees aren't part of the story, but cattle. As we mentioned, one of the sources for producing SAF is animal fat. Reuters, through a thorough investigation, discovered that a Texas refinery that sells the green fuel to U.S. airlines allegedly purchased the fat from cattle raised on illegally deforested land in the Amazon.

The company is called Diamond Green Diesel, which has invested hundreds of millions of dollars in a refinery in Port Arthur, Texas, that turns tallow —the name given to beef fat—into "clean" jet fuel. The deal is even more fraught because in 2022, the company collected a whopping $3 billion in tax credits for biofuel production. The investigation revealed that the tallow was generated by two Brazilian factories that supplied thousands of tons of fat, which in turn were purchased by slaughterhouses that allegedly sourced animals from illegally deforested farms in the Amazon rainforest. In short, a vicious cycle .

Also because airlines, which in turn buy SAF, obtain credits for reducing their emissions , because the Diamond Green Diesel plant is certified under an agreement involving the United Nations. In other words, everyone involved benefits, but in a dirty way. Or at least in a less than transparent way, to the detriment, once again, of the poor green lung of the world, in which the Brazilian beef industry is significantly involved.

Meanwhile, judicial authorities in Brazil have turned the spotlight on the matter. "Companies that profit from raw materials from a supply chain that involves deforestation are also responsible for these illegalities ," Ricardo Negrini, the Brazilian federal prosecutor who has opened a series of investigations into the beef industry, told Reuters. The companies involved, however, declined to comment when asked detailed questions about the Brazilian tallow supply chain.

While airlines are under pressure from their respective national regulatory authorities to achieve their CO₂ emissions reduction and elimination targets by 2050 (as is the case with the auto industry), it is also true that SAF, or any other sustainable aviation fuel, to be eligible for credits, must not come from biomass from land deforested after 2008 or from protected areas under international agreements.

Pushing airlines toward net zero is CORSIA, an acronym for Carbon Offsetting and Reduction Scheme for International Aviation , a market-based mechanism developed and managed by the International Civil Aviation Organization , the United Nations agency that oversees the conventions on international civil aviation. While airlines' participation is currently voluntary , from 2027 it will be mandatory in order to redeem carbon offset credits.

And the use of SAF is a fundamental pillar of CORSIA. In fact, according to some representatives who participated in drafting CORSIA, interviewed by Reuters, the production of tallow for SAF would not directly lead to an increase in livestock production, and thus deforestation in the Amazon, because it is assumed that livestock would be raised for meat anyway, and tallow is simply an inevitable and secondary byproduct of that process.