Humanity is working to repair the damage done to the planet. Carbon capture and storage (CCS) is one of the most effective tools in the fight against climate change. Oceans and forests naturally store carbon, and since 1996 society has sought to contribute its part. Yet the overall amount of carbon captured and stored over the years appears smaller than previously estimated, with a range roughly between 19% and 30%.
That conclusion comes from a research group at Imperial College London, published in Environmental Science and Technology Letters. The researchers point out that there is no common framework for measuring sequestration rates, meaning estimated tonnes of CO2 held from 1996 to 2020 may be overstated. They warn that such figures can create a false impression of the technological contribution to addressing climate change.
The analysis relies on data from 26 CCS facilities worldwide, rather than calculating the actual carbon captured and stored in each facility.
CCS, also known as carbon capture and storage, is a technique used to remove carbon dioxide from the atmosphere or prevent its release in the first place. It involves capturing CO2 from industrial processes and energy production, transporting it via pipelines or ships, and injecting it into geological formations for long‑term isolation from the atmosphere.
Mitigate climate change
CCS is considered a cornerstone of climate change mitigation. The lead author notes its importance but stresses that without a standardized method for reporting results, the data cannot reliably guide policy or investment decisions. A consistent framework would enable a more proactive approach to reducing global warming.
One illustrative example is the Orca facility operated by Climeworks in Iceland, which demonstrates the practical potential of CCS in real-world conditions. This example underscores the need for robust, comparable data to inform future deployments and monitoring.
The researchers argue that a centralized, uniform reporting system is missing. There is no single international standard detailing the actual rates of carbon captured, transported, and stored—and this gap hampers the ability to monitor progress and identify where improvements are needed. Researchers emphasize that reliable information is essential for tracking mitigation progress and addressing technical issues as they arise.
Co‑author Samuel Krevor notes that there is no global consensus on how much CO2 has been stored so far beyond academic estimates. He advocates for clear, common parameters to determine current status and trajectory. A unified approach would clarify how CCS contributes to a broader climate strategy and where gaps still exist.
To reach their conclusions, the study examined CCS activity from 1996 to 2020 across 20 of the 26 plants in operation during that period. Researchers drew on diverse sources to assemble a comprehensive view of capture and storage activity and found that about 197 million tonnes of CO2 were stored during this timeframe. This figure highlights the significance of CCS but also the importance of rigorous auditing to ensure accuracy and usefulness for policy and industry planning.
Third‑party inspections required
When the researchers compared their estimates with plant‑reported data, a gap emerged. Relying solely on reported capacity tends to overstate the amount of sequestered carbon by roughly 19% to 30%. The roughly 200 million tonnes captured represents a meaningful achievement, yet it cannot stand as a definitive scientific accounting without independent verification.
The study reinforces the idea that capture capacity alone is not the best metric for assessing long‑term storage performance. Authorities and researchers should pursue a more tailored metric that reflects actual flow from capture through storage, including downtimes, transport limits, and the frequency of independent audits to improve data quality.
Analysts stress the importance of including key indicators in reports, such as projected and maximum capture rate capacity, annual CO2 capture, transport and storage, facility downtimes, and the inclusion of third‑party audits. Such details would greatly enhance the reliability of information guiding policy, investment, and environmental planning.
Source: earth‑planet space atmosphere and climate science report. It is cited here to acknowledge the research foundation for these insights and to provide a basis for ongoing discussion and improvement in CCS data reporting. Researchers advocate adopting standardized methods and transparent reporting to strengthen the global response to climate change and to ensure CCS contributes meaningfully to emission reductions [citation attribution: earth‑planet space, 2022].