Emission Impossible: Cryptographically Verifiable Carbon Emissions Reporting for Cloud Computing

Abstract

Cloud providers need to report to their customers what carbon emissions have arisen from their use of computing resources, so that customers can include them in their own mandated emissions reporting. At present, these reports are neither verifiable nor audited. We show how a data centre operator can produce cryptographic zero-knowledge proofs to each customer that the emissions reported to that customer are accurate, without the customer being able to learn sensitive information about the data centre operator or other customers. Our approach is scalable, costing a data centre operator with one million customers an estimated $150 USD per month plus $0.01 USD for each customer who requests a verifiable emissions report. For customers, a proof is 37 KiB in size, and verifying it takes less than a second. By making emissions reports more trustworthy, we hope to give companies and policymakers the data they need to push towards decarbonisation.