Ten years after COP21 and the Paris Agreement, and halfway to 2030, global emissions remain off track. Companies with science-based targets are making progress, but financial, technical, and accounting uncertainties are slowing things down.
The Science Based Targets initiative‘s (SBTi) draft Corporate Net Zero Standard Version 2 (CNZS V2) could help speed up progress. This newly released draft explicitly allows companies to use Environmental Attribute Certificates (EACs), like Sustainable Aviation Fuel (SAF) Book & Claim certificates, as part of pathways to science-based targets. Companies can now purchase SAF even more confidently, making science-based action achievable.
Our SAF Standards & Reporting Manager, Amelia Ransome, takes a closer look at what the draft means for companies on the path to net-zero.
“Focus and flexibility”
Version 2 introduces what SBTi refers to as a more “focused and flexible” Scope 3 framework, which is good news for the SAF community. As it stands, companies face limited options to purchase SAF directly due to infrastructure or production constraints. With SAF and Book & Claim systems, verified emission reductions are still achievable even when physical supply chain options are limited.
SBTi now allows what they call “sector-level interventions”, collective or market-based mechanisms that drive decarbonization beyond a company’s direct control. For SAF, Book & Claim can play a transformative role.
When companies cannot physically source enough low-carbon goods, they may procure “unbundled EACS”, like SAF certificates, to meet what SBTi calls “volume-alignment targets” and support emerging low-carbon sectors. This acknowledges that credible market-based mechanisms are legitimate decarbonization tools, as long as integrity principles are upheld.
Getting integrity right
While recognizing SAF certificates is a step forward, SBTi highlights areas needing more clarity. Annex E of the draft sets ‘high-level integrity principles’ for EAC issuance (accuracy, exclusivity, verifiability, traceability, attribution, expiry) and transactions (transparency, avoidance of double-claiming).
For SAF players, these principles can shape the integrity and interoperability of future systems. Engagement in the consultation makes sure frameworks are credible, practical, and supportive of scale-up, and aligns with how SAF registries are evolving – using digital platforms, strict sustainability criteria, audit trails, and expiry rules to uphold environmental integrity.
From ambition to action
CNZS V2 shifts focus from technical updates to governance and accountability. Companies must now:
- Secure board approval for climate targets.
- Align policy engagement with net-zero goals.
- Publish credible transition plans.
For the SAF industry, this signals a move from voluntary pledges to strategic priorities, which in turn could build investor confidence in both companies and the decarbonization solutions, like SAF, that support their goals.
What is missing?
There are two areas where we hope to see greater clarity following the public consultation.
Scope 1 and the role of Book & Claim: Beady eyes may have noticed that the term “unbundled energy environmental attribute certificates” appears only under the Scope 3 chapter, while Scope 1 refers to “contractual instruments conveying energy attributes”. This distinction means that, for airlines, purchasing SAF via Book & Claim is not yet recognized as an acceptable Scope 1 reduction lever under CNZS V2.
However, SAF remains highlighted as a key decarbonization tool in SBTi’s Aviation Guidance (2021), which is scheduled for revision to align with updated scientific evidence. This suggests further exploration into whether Book & Claim could be formally accepted.
In practice, Book & Claim is sometimes the only viable route for airlines to access SAF, as limited production capacity and infrastructure prevent physical delivery to many airports. By unbundling the environmental attribute of SAF from its physical fuel, airlines can continue to decarbonize operations while financing producers, even when they cannot use the fuel locally. We hope this approach will be recognized in future CNZS updates.
Transition clarity: While the draft outlines a transition period for adopting Version 2, it is unclear whether mechanisms such as SAF certificates can apply to existing science-based targets during this phase. Without clarity, companies may delay action until CNZS V2 becomes mandatory in 2028, by which time, the window for achieving 2030 goals will be closing. Recognizing and rewarding early investment in credible decarbonization solutions like SAF is vital to maintain momentum now, not later.
We believe credibility builds confidence
At SkyNRG, we welcome SBTi’s recognition of sector-level interventions and its focus on credible market mechanisms. EACs like SAF certificates are verifiable, traceable tools that push aviation decarbonization forwards and build investor confidence in sustainable fuel production.
Now is the moment for the SAF community to have a strong, unified voice in shaping what comes next.
Have your voice heard
The SBTi consultation on CNZS V2 is open until December 8, 2025. For the SAF community, this is a chance to help define credible, scalable market-based mechanisms that contribute to science-based climate targets. Feedback on integrity principles, credibility safeguards, and transition-plan requirements will directly influence the final standard and the legitimacy of the SAF market.
Fill in the survey here.
