How a litre of fuel becomes a tradable claim
The SAF market runs on a book-and-claim model. Understanding it explains where the value sits — and where the gap is.
Why the fuel and the credit separate
The core of the book-and-claim model lies in the physical and environmental decoupling of Sustainable Aviation Fuel. While the physical molecules are mixed into the existing fuel infrastructure at the production site, the environmental benefits are 'booked' into a registry as digital credits. This separation allows the fuel to flow through the most efficient logistics channels while the credits are traded globally, enabling companies to claim emissions reductions without needing the physical fuel to reach their specific airport. This system solves the geographical mismatch between SAF production centers and global aviation hubs, accelerating market adoption and investment in green energy.
Four roles, two flows
SAF producer
SAF supplier
Fuel → · Cash ← · Certificate →
Airline
Corporate buyer
Role
What they do
SAF producer
Manufactures the fuel from waste or renewable feedstock
SAF supplier
Blends and distributes it into the aviation fuel supply
Airline
Buys and burns the physical fuel
Corporate buyer
Pays the premium above fossil jet fuel and receives the certificate
In this ecosystem, two distinct payments support the industry. The airline pays for the physical fuel (energy), while the corporate buyer pays the 'green premium' for the environmental attribute (credit). This dual-funding mechanism bridges the cost gap between conventional jet fuel and SAF, creating a sustainable financial loop that incentivizes production and adoption across the entire value chain.
The model is already operating at scale
Beginning in 2020 through 2024, the book-and-claim mechanism matured from a theoretical framework into a robust, high-volume market reality. Major global logistics networks, aviation fuel consortiums, and sustainability programs have successfully deployed this architecture to securely trade environmental attributes across diverse geographies. This operational maturity demonstrates that financial barriers to scale have been addressed, providing the necessary liquidity to de-risk long-term capital investments in SAF production.
Public market illustration based on publicly announced transactions. WATT Labs was not a party to these agreements.
What the loop is missing
The current book-and-claim ecosystem faces key operational and market access barriers, creating a significant infrastructure gap, creating a significant infrastructure gap. Without a common digital rail to verify and clear transactions in real-time, the market remains fragmented and opaque. This technical friction restricts participation to a few dominant institutional players, preventing the broad-based liquidity needed to scale SAF adoption globally.
By and large, these missing linkages result in market concentration among a handful of large buyers who can navigate bespoke integrations. The absence of an open, standardized settlement layer means smaller airlines and corporate partners are effectively locked out. Solving this gap is critical to democratizing access to carbon credits and ensuring the financial loop can support the industry's net-zero transition targets.
A settlement layer for SAF certificates
WATT Labs is building the tokenisation infrastructure and associated tools for Sustainable Aviation Fuel (SAF) certificates. By transforming environmental attributes into digital tokens, we enable certificates to be transferable, verifiable, and auditable as standard financial instruments.
Liquidity
Certificates that can move between holders rather than sitting inside a single bilateral contract.
Transparency
A verifiable record of origin, volume, and retirement status.
Onboarding
A route into the SAF market for corporates below the scale of a ten-year offtake agreement.
We are already a registered trading participant on four global carbon exchanges. The tokenisation layer is the next piece.