This is a centralised register of annual rates of CO₂ stored underground from operational projects worldwide. This initiative, funded by the UK Royal Academy of Engineers and supported by a consortium of stakeholders from academia, industry, and government, obtains data directly from operators as well as from publicly available information, providing a standardised register of the annual amounts of stored CO₂.

Due to the importance of carbon capture and storage (CCS) in modelled climate mitigation pathways, the feasibility of achieving these rates by mid-century is central to our understanding of the potential to avoid dangerous climate change (Figure 1). With increasing numbers of industry-scale storage projects operating around the world, data through which project performance, and scale-up potential, may be evaluated are becoming available.

Most operating CCS project chains publicly report their achieved rates of capture, transport, and storage (Figure 2 ). However, these data are reported via a wide variety of outlets ranging from governmental databases to company press releases. The variation in the reporting avenues, time periods, information type, and quality assurance creates challenges in both accessing information and analysing data across projects.

A centralised register of self-consistent information on annual storage performance will have many beneficiaries. Carbon storage project operators will benefit from visibility and clarity on their project performance. Investors and the business sector will benefit from increased confidence in the technology as a climate change solution and a viable business with compliance. Policy makers and the publics require this information to evaluate current and potential climate change mitigation provided by underground carbon storage.