Scientists from Radboud University in the Netherlands came out with an assessment on the life cycles of more than 40 carbon capture utilization and storage (CCUS) processes and draw the conclusion that most of them do not reduce emissions sufficiently.
32 out of the 40 technologies were found to emit more carbon than they captured. Just four methods appeared to be ready for use while also emitting low amounts of carbon. The scientists assessed the carbon capture technologies against three criteria: could they permanently store CO2; does the CO2 they collect come from atmospheric and natural sources; and does the process have zero emissions.
The researchers also concluded that it is not possible for most carbon capture and utilization methods to sufficiently reduce industrial CO2 emissions in time to support the Paris Agreement targets.
The reasons for that are some technologies do not reduce CO2 emissions enough throughout their life cycle, and others will simply not be ready in time. The 2030 targets are pretty tight and many carbon capture projects are still in development so it will take years before they become operational.
In the assessment, the analysts used assumptions about future electricity mix that could change. They assumed the electricity would be completely renewable by 2050 which under a more pessimistic scenario could make CCUS even more carbon intensive.
“CCU appeals to policy-makers and the public because it’s seen as a circular economy. There are some very positive perceptions of CCU, but the point that [the researchers] are making is that not all CCU technologies are the same,” said Guloren Turan at Global CCS Institute, an international think tank that promotes the use of carbon capture technologies.
Ultimately, researchers recommend it is worth concentrating more efforts on storing carbon for thousands of years, rather than utilizing it in the industry. Some scientists claim this approach would be better in terms of taking CO2 out of the climate.
Assessments on the emissions reduction technologies like carbon capture are needed to help policy-makers make better decisions in terms of solutions they could invest in that would help achieve climate goals. Choosing methods that do not cut greenhouse gasses sufficiently that would be going on for decades would be a failure in CO2 reduction efforts.