Carbon Capture and Storage Systems, Overestimated Carbon Capture for 25 years

What is carbon capture and storage

Carbon capture and storage (CCS) or carbon capture and sequestration is a type of infrastructure and technology for capturing carbon emitted from a source, and storing it. The source is usually industrial, like a cement kiln which are responsible for massive amounts of emitted carbon because of construction’s outsized role in the world. The storage is usually a geological formation.

Is carbon capture and storage an economical technology

CCS technology has been around a long time, and is liked by industry best when the carbon dioxide is coupled to a process to aid in the production of a high value product. Otherwise, as is the foundational problem of combating climate change, the capture of carbon generates a low value product and is a poor incentive by itself.

Imperial College report says CCS is less effective than previously thought

A new report from Imperial College London that found that the carbon capture and storage technology is not as effective as previously thought. The report found that the lack of consistent reporting frameworks lead to overestimates of the technology’s ability to fight climate change. The article quotes the lead author of the report, Yuting Zhang, who says that without a centralised reporting framework, we are not able to effectively tackle climate change.

“Policymakers should embrace a centralised reporting database that includes rates of carbon capture, transport, and storage, including quality assurance measures like independent auditing” said lead author of study Yuting Zhang.

Reporting in the form of capacity rather than actual carbon stored is a problem

The article also notes that the most up-to-date information on capture rates comes from the annual reports and databases of thinktanks, but these only report CCS activity as facility capacity rather than actual carbon stored. The authors urge better guidance and definition around carbon capture in order to create an international consensus.

Study of 20 CCS plants added quantitative evidence

The researchers then looked at the capture and storage rates of 20 of the 26 CCS plants worldwide from a variety of publicly available sources recorded between 1996 and 2020 and found that underground storage provided CO2 mitigation of around half of the emissions avoided by solar panels in the USA in 2019.

Even the most authoritative source overestimated storage rates

The researchers found that the most authoritative source of information on CCS achievements, which report carbon capture capacity, overestimate storage rates by between 19 and 30 per cent. They argue that requiring facilities to report actual capture rates would tell us more precisely how well CCS is working and put us in a much better position to address the climate crisis.

Measure carbon captured rather than the proxy of capacity to overcome problem

Co-author Visiting Professor Chris Jackson from Imperial’s Department of Earth Science and Engineering said: “CCS is a relatively new climate technology that is already contributing significantly to the fight against climate change. However, we show that capture capacity is not the best way to measure storage rates, and that governments should ideally enforce the use of the bottom-line metric of carbon captured.”

Correct reporting of CCS performance will improve deployment

Consistent reporting on CCS storage performance can better facilitate the modelling of large-scale deployment of CCS to monitor short-term emission reductions and long-term resource requirement of the technology. The researchers say reporting frameworks should include key details like intended capture rate capacity, maximum capture rate capacity, annual capture of CO2, annual transport of CO2, annual storage of CO2, quality assurance measures such as third-party auditing, and reasons for any offline periods where the CCS facility could not operate as intended. 

This work was funded by Engineering and Physical Sciences Research Council (EPSRC), part of UKRI.

Original study: Yuting Zhang, Christopher Jackson, and Samuel KrevorEnvironmental Science & Technology Letters

https://doi.org/10.1021/acs.estlett.2c00296