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Glossary
The terms buyers meet, defined plainly: insetting, Scope 1 and Scope 3, chain of custody, RSB, ISCC, and SBTi.
- SAF (sustainable aviation fuel)
- Jet fuel made from sustainable feedstocks rather than fossil crude. It reduces emissions on a lifecycle basis, not at the tailpipe.
- Book and Claim
- A system that separates the environmental benefit of a lower-emissions fuel from the physical fuel. A buyer can fund it in one place and claim the verified reduction, even where the fuel itself isn't available.
- Insetting
- A reduction made inside your own value chain, where the emissions happen. A SAF certificate is insetting, not an offset and not a carbon credit.
- SAF certificate (SAF Scope 3 certificate)
- The instrument that records the verified reduction from a batch of SAF and assigns it to one owner. The corporate version records a Scope 3 reduction.
- Scope 1
- Emissions from sources a company controls directly, such as an airline burning fuel in its own aircraft.
- Scope 3
- Indirect emissions in a company's value chain, including employees' business travel. This is where corporate SAF claims sit.
- Chain of custody
- The tracked, auditable record of a fuel and its attribute from feedstock to final claim, so the reduction can be traced and proven.
- Registry retirement statement
- The formal registry record that a defined quantity of SAF was used, assigned to one buyer, and retired so it can't be claimed again.
- Lifecycle emissions
- Emissions counted across the whole life of a fuel, production, transport, and combustion combined, rather than only at the point of burning.
- Tenor
- The length of a contract. Producers need a firm demand tenor of roughly ten to fifteen years to make a new plant bankable.
- Offtake
- A long-term agreement to buy a producer's fuel, the firm, long-dated demand that lets a plant get financed.
- Feedstock
- The raw material a fuel is made from, such as used cooking oil, waste fats, or technical corn oil.
- RSB (Roundtable on Sustainable Biomaterials)
- An independent sustainability certification standard. FEG is certified to it.
- ISCC (International Sustainability and Carbon Certification)
- An independent sustainability and carbon certification standard. FEG is certified to it.
- SBTi (Science Based Targets initiative)
- The body that sets corporate climate-target standards. Its Corporate Net Zero Standard V2 recognises SAF certificates for Scope 3 through book and claim, mandatory for new targets from 2028.
- CORSIA
- ICAO's offsetting and reduction scheme for international aviation. It is a compliance instrument, distinct from insetting.
- ReFuelEU Aviation
- EU regulation requiring fuel suppliers to blend a rising share of SAF. It governs airlines and suppliers, not a corporate's voluntary Scope 3 claim.