Brazil’s largest energy giant tests Cardano to fix carbon double-counting

Petrobras, Brazil's state-controlled energy company, is testing Cardano to track sustainable aviation fuel benefits and prevent double-counting.

The Cardano Foundation said on Sept. 30 that an ongoing research and development collaboration had delivered applications for sustainable aviation fuel (SAF) and Diesel R, Petrobras' renewable fuel brand.

The SAF project addresses a problem that arises when the buyer of a fuel's environmental benefit is different from the buyer or user of the fuel itself. Its Book-and-Claim model lets an airline, company, or passenger receive that benefit even when the SAF is produced or used elsewhere.

Petrobras developed the SAF platform with PUC-Rio University's Ledger Labs and the Cardano Foundation. According to the Foundation's case study, it represents SAF environmental attributes as standardized CS-SAF tokens on Cardano.

Those tokens can be created, transferred, checked, and retired. Retirement prevents the same attribute from being claimed again, while the digital record traces the allocation back to the original fuel certificate.

The crypto analogy is double spending: preventing reuse of a digital asset, applied here to an environmental claim.

Travelers can enter departure and destination airports, calculate a CS-SAF allocation and receive a certificate showing their route, distance and allocation, the Foundation says. That claim remains linked to the original SAF certificate.

The tokens carry metadata aligned with CORSIA, the Carbon Offsetting and Reduction Scheme for International Aviation.

In guidance published June 16, the Roundtable on Sustainable Biomaterials says Book-and-Claim changes neither the physical fuel a buyer uses nor its associated emissions. Airlines should disclose supported reductions separately from operational emissions.

Different value-chain participants can make distinct claims, as long as their disclosures do not misrepresent the overall reduction.

Cardano usage beyond aviation

The Diesel R project, developed with PUC-Rio, proposes checkpoints across production, transportation and use. Its aim is a continuous fuel-lifecycle record that could support Scope 3 reporting, which covers indirect emissions across a company's wider value chain.

That would connect information held by suppliers and logistics providers, giving emissions reporting a more traceable supply-chain history. The Foundation describes this architecture as a proposed model within the R&D work.

The SAF platform illustrates how Cardano can record the allocation and retirement of environmental benefits. Commercial use remains unquantified, as the Foundation's disclosures provide no transaction volumes or revenue figures.