Brazil's state-controlled energy company Petrobras is testing the Cardano blockchain in two research projects to trace environmental claims tied to sustainable aviation fuel and its partly renewable Diesel R. The projects were announced on September 30 by the Cardano Foundation and developed through its ongoing research collaboration with Petrobras and PUC-Rio's Ledger Labs. The aviation project focuses on sustainable aviation fuel, a lower-carbon alternative to conventional jet fuel that can be used in existing aircraft and airports, while the diesel project covers Petrobras' diesel made partly from renewable materials such as vegetable oils or animal fats. According to the Cardano Foundation, the aviation project separates fuel use from the allocation of environmental benefits, with the diesel project linking production, transport, and use records to support emissions reporting.
The aviation project addresses the book-and-claim model where airlines can pay for environmental benefits of sustainable fuel without necessarily using it. As reported by the Cardano Foundation, the application uses Cardano to record where each benefit originated, who received it and when it was claimed, helping prevent the same emissions reduction from being counted twice. In its accompanying SAF case study, the organization describes a certificate-checking process that takes place before digital records enter the system, with certificates checked against the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) and other recognized standards. Once verified, the certificates become standardized tokens carrying environmental attribute information, with participants able to issue, transfer, and inspect the tokens before retiring them when the associated benefit is claimed. The Cardano Foundation identifies CS-SAF as the digital token representing the aviation fuel's environmental benefit, while the system describes assigning tokens to airlines or individual journeys using emissions calculations.
The diesel project would record information at each stage of production, transportation and use, creating a comprehensive history of the fuel's journey that could help companies report Scope 3 emissions across their suppliers and customers. According to Petrobras' product documentation, the company sells Diesel R to fuel distributors that supply service stations in Brazil, with the resulting fuel containing a renewable portion produced by processing petroleum-based diesel alongside vegetable oils or animal fats. The Cardano Foundation places particular attention on Scope 3 emissions, which covers indirect emissions across a company's value chain, noting that necessary information can sit in separate supplier, logistics and external systems. The connected records would enable companies to consult fuel history when preparing emissions accounts, with the system designed to trace data used in emissions reports.
Both projects remain in the research stage, with no disclosed timeline for broader deployment or details about the fuel volumes covered. According to the Cardano Foundation, the diesel model is described as proposed, and the announcement disclosed neither fuel volumes covered nor a timeline for wider use. However, Frederik Gregaard, chief executive of the Cardano Foundation, noted that Brazil has been one of the most consistent adopters of Cardano, from SERPRO in government to SENAI in industry, with institutional interest in Cardano growing significantly. Rafael Fraga, the Foundation's Latin America business development lead, emphasized that "the energy transition will depend as much on trust as it does on new fuels," with increasingly complex supply chains making the origin, movement and reliability of environmental data important to companies using it.
The projects align with Cardano's recent integration with x402, a payment standard that lets applications and AI agents pay for data or computing services as they request them. As reported by the Cardano Foundation, Cardano joined x402 this month, with its initial payment-processing software having been tested on Cardano's pre-production network, though commercial use on the live blockchain still needs to be demonstrated. The foundation emphasized that it's never been a better time for enterprises to consider what this technology offers, with growing institutional interest in Cardano's on-chain provenance and traceability capabilities. The current partnership builds on earlier Brazilian collaborations, including the Cardano Foundation's April 2025 research agreement with PUC-Rio that initially focused on renewable fuel production and supply chains, and the Cardano Foundation's March 2025 partnership with SERPRO that included bringing Cardano Academy training to the Brazilian government technology provider's 8,000 employees.
