One implementation of Green Proofs is the Maritime Book and Claim (MBC) registry created by the Energy Web Foundation in collaboration with Rocky Mountain Institute and MMMCZC. The MBC registry brings transparency and credibility to claims about the carbon impacts of maritime shipping voyages that use lower-carbon shipping fuels.
Decarbonizing maritime shipping is a critical effort because the sector accounts for some three percent of global emissions.
The registry includes the following main functionalities:
Issuance: The operator or owner of a ship can register the usage of low-emissions fuel. Multiple admins verify the request and approve the issuance of a ceritifcate representing the carbon impact of the fuel.
Transfer: The certificate can be transferred to any actors involved in shipping, including freight forwarders or cargo owners.
Retirement: actors can retire the certificate, which means that they can claim in their sustainability reporting that low-emission fuels have been used in transportation.
Transparency: After actors have retired the certificates, the information becomes public (after sensitive information is removed).
As an example, if you order a pair of shoes online, that pair typically is shipped thousands of kilometers from its place of manufacture to you. The MBC registry allows the various parties involved in the transportation to transparently and credibly show the carbon savings of shipping with sustainable fuels.