A joint investigation by Unearthed, Repórter Brasil and partners has put a deeply uncomfortable question on the table: is the beef tallow that ends up in EU-certified “green” diesel and Sustainable Aviation Fuel (SAF) really as clean as the paperwork claims? According to their reporting, at least €1.24 billion worth of renewable fuel deliveries from one US supplier to Belgium and the Netherlands between 2025 and April 2026 can be traced back, via a Brazilian rendering subsidiary, to a slaughterhouse operator facing 31 lawsuits over illegal deforestation in the Jaci-Paraná extractive reserve in Rondônia.

The companies involved deny wrongdoing, and it remains unclear how widespread the problem is. But even as an allegation, the story exposes a structural weakness that should concern everyone working on cleaner fuels — including those of us in the Power-to-X and e-fuels community who use no animal fats at all.

The traceability gap at the heart of the system

Under the EU’s Renewable Energy Directive, transport must cut its greenhouse-gas intensity by 14.5% by 2030 — a target that is essentially impossible without large volumes of biofuels and synthetic fuels. To enforce sustainability, the EU relies on certification schemes such as ISCC EU to trace feedstocks from origin to fuel.

For beef tallow, however, the trail goes cold at the rendering plant. Tallow is classified as a waste or by-product of meat production, not as a product of cattle farming. The farms where the animals were raised — and where any illegal deforestation would have happened — fall outside the certification system. ISCC has confirmed this carve-out to the investigating journalists.

The consequence is uncomfortable: a fuel can be certified as delivering up to 80% lifecycle emission savings even if the underlying animal was raised on illegally cleared Amazonian land. As Anna Krajinska of Transport & Environment told the investigators, if the upstream emissions of deforestation were properly counted, the resulting fuel might not even clear the EU’s greenhouse-gas reduction threshold.

And the EU’s flagship Deforestation Regulation (EUDR), which enters into application on 30 December 2026, covers meat, leather and hides — but not beef tallow. The very substance at the heart of this story is, for now, legally invisible.

Why this is a Power-to-X problem, even though e-fuels don’t use tallow

Here is where it gets uncomfortable for our own industry. E-fuels, e-SAF and other Power-to-X products are not biofuels. They are produced from renewable electricity, water and captured CO₂. No cows, no tallow, no rendering plants, no Amazonian supply chains. From a technical and sustainability perspective, the two pathways have almost nothing in common except the regulatory bucket they share: “renewable” or “sustainable” fuels under ReFuelEU Aviation, the Renewable Energy Directive and similar frameworks.

And yet, in the eyes of the public, of politicians, and of many investors, that distinction is far too subtle. When a headline reads “EU ‘green’ fuel linked to Amazon deforestation”, the average reader does not parse out which molecules came from which feedstock. They register one thing: another sustainability label that turned out not to mean what it said.

This is the textbook definition of reputational contagion — also known in risk and marketing literature as a negative spillover effect, or, in everyday language, guilt by association. When one actor or sub-segment in an industry is exposed for misconduct, the reputational damage does not stay neatly contained. It spreads across the entire category, hitting even those companies and technologies whose practices are genuinely sound.

We have seen this dynamic before. The “dieselgate” emissions scandal did not just hurt the carmaker at its centre; it cast a long shadow over diesel as a technology and over the credibility of automotive emissions testing as a whole. The 2023 OCCRP investigation into mislabelled US soy-based biodiesel sold into Europe as “used cooking oil” damaged trust in waste-based biofuels far beyond the single Bosnian company involved. Each new story chips away at the social licence of the entire sustainable-fuels space.

What is at stake for e-SAF and Power-to-X

The risks of reputational contagion for our sector are concrete, not abstract:

  • Political backlash and regulatory rollback. If “green” fuels become synonymous with hidden deforestation in the public debate, ambitious mandates — including the ReFuelEU SAF blending quotas rising to 6% by 2030 and 70% by 2050 — become politically vulnerable, even for fuel categories that have no link to the problem.
  • Investor and offtake uncertainty. E-SAF and e-fuel projects depend on long-term contracts and patient capital. Reputational shocks to the broader “sustainable fuels” category make banks, airlines and corporate offtakers more cautious about all renewable fuel offtake agreements, not just biofuel ones.
  • Tighter, blunter rules. Regulators tend to react to scandals with horizontal tightening: more paperwork, more audits, more conservative default emission factors applied across the board. E-fuel producers, who already operate on thin margins and complex permitting timelines, would absorb part of the compliance cost of a problem they did not cause.
  • Stakeholder fatigue. Communities, NGOs and journalists who repeatedly encounter “green fuel” stories that turn out to involve deforestation, fraud or greenwashing become structurally more sceptical of every new fuel project — including genuinely transformative Power-to-X pioneers in Switzerland and beyond.

SPIN Perspective

From the perspective of the Swiss Power-to-X Collaborative Innovation Network, three points matter.

First, this story is a warning, not an indictment. The Unearthed / Repórter Brasil investigation does not (and could not) implicate e-fuels or Power-to-X. But it shows how thin the line is between a credible sustainability label and a discredited one — and how quickly that thin line can be erased in the public conversation.

Second, e-SAF and e-fuels have a genuine traceability advantage — and we should make far better use of it. A Power-to-X plant has a finite, auditable list of inputs: renewable electricity (with guarantees of origin), water, and CO₂ from a known point source or direct air capture. There is no Amazon ranch hidden three layers up the supply chain. Our sector should actively turn this into a competitive narrative: not just “low emissions on paper”, but fully traceable, physically verifiable, deforestation-free by construction.

Third, the policy response must distinguish between feedstock pathways, not just between “fossil” and “non-fossil”. Lumping e-fuels, advanced biofuels, waste-based biofuels and tallow-based fuels into a single regulatory bucket made sense when volumes were small. As volumes scale into the billions of euros, it is becoming a liability for the genuinely sustainable end of the spectrum. SPIN will continue to advocate, in Bern and Brussels, for sustainability frameworks that reward verifiable upstream integrity — not just downstream certification stamps.

If the allegations around tallow-based fuels prove true, the worst outcome would be a public backlash that punishes the wrong technologies. The best outcome would be a regulatory and industry reset that finally distinguishes between fuels that claim to be green and fuels that are — by construction — clean. Power-to-X belongs firmly in the second category. It is in everyone’s interest, including the public’s, that the rules and the narrative catch up to that reality.

Source of the underlying investigation: Belle de Jong, Charlotte Teunis, Naira Hofmeister, Hyury Potter, Gabriele Di Donfrancesco — published with the support of Journalismfund Europe, in partnership with Unearthed and Repórter Brasil.