Turning Challenge into Opportunity 2025

How book-and-claim can accelerate expansion of green maritime fuels Book-and-claim mechanisms complement flexible, aggregated demand models in three pivotal ways (see Figure 4): –Infrastructure bypass: By decoupling fuel use from fuel location, book-and-claim mitigates the unevenness of bunkering infrastructure. For example, a shipowner in Africa or South America can purchase clean fuel certificates, even if the nearest port lacks supply. –Supplier diversity: Book-and-claim integrates fragmented suppliers into a common marketplace, allowing large and small producers to issue credible claims for their volumes, widening participation and reducing market concentration. –“Financeability”: Traceable, third-party-verified certificates generate confidence for investors and regulators, making offtake commitments more bankable even in early, geographically limited markets. Book-and-claim – three pivotal advantages FIGURE 4 Aggregated demand Infrastructure bypass – Decouples clean fuel use and purchases from fuel location – Mitigates unevenness of bunkering infrastructureSupplier diversity – Integrates fragmented suppliers into common marketplace – Widens producer participation and reduces market concentrationFinanceability – Traceable, verified certificates generate confidence for investors – Makes offtake commitments more bankable Book-and-claim Book-and-claim: design considerations –Attribute boundaries should be clearly defined, specifying fuel type, lifecycle emissions covered (well-to-wake), geographic origin and certificate validity period. –Allocation and retirement rules should ensure units can only be claimed once, with transparent retirement events accounted for by established registries to prevent double counting. –Auditing and registries should be standardized, with third-party verification, unique certificate IDs and interoperability across registries; consider building on lessons from SAF pilots. –Accounting alignment should map claims to accepted GHG reporting frameworks and disclosure standards, enabling both shipowners and cargo owners to credibly integrate claims into scope 3 accounting. –The credibility of book-and-claim depends on robust governance. Concerns remain over double counting, registry interoperability and ensuring that claims correspond to actual lifecycle emissions reductions. Industry initiatives – such as the Maersk Mc- Kinney Møller Centre for Zero Carbon Shipping’s work on transparency frameworks and the GCMD’s trials on digital verification (in this case specific to biofuels) – are actively tackling these Turning Challenge into Opportunity: Supplier Voices from Heavy-Emitting Sectors 20