Major boost in carbon capture and storage essential to reach 2°C climate target

The idea behind carbon capture and storage (CCS) technology is to capture carbon dioxide then store it deep underground. Some applications of CCS, such as bioenergy with CCS (BECCS) and direct air capture and storage (DACCS) actually lead to negative emissions, essentially "reversing" emissions from burning fossil fuels. CCS technologies play an important role in many climate mitigation strategies including net-zero targets. However, the current use is negligible.

"CCS is an important technology for achieving negative emissions and also essential for reducing carbon emissions from some of the most carbon-intensive industries. Yet our results show that major efforts are needed to bridge the gap between the demonstration projects in place today and the massive deployment we need to mitigate climate change," says Jessica Jewell, Associate Professor at Chalmers University of Technology in Sweden

A new study titled, 'Feasible deployment of carbon capture and storage and the requirements of climate targets',conducted a thorough analysis of past and future growth of CCS to forecast whether it can expand fast enough for the Paris Climate Agreement. The study found that over the 21^st century, no more than 600 Gigatons (Gt) of carbon dioxide can be sequestered with CCS.

"Our analysis shows that we are unlikely to capture and store more than 600 Gt over the 21^st century. This contrasts with many climate mitigation pathways from the Intergovernmental Panel on Climate Change (IPCC) which in some cases require upwards of 1000 Gt of CO2 captured and stored by the end of the century. While this looks at the overall amount, it's also important to understand when the technology can start operating at a large scale because the later we start using CCS the lower the chances are of keeping temperature rise at 1.5°C or 2°C. This is why most of our research focused on how fast CCS can expand," says Tsimafei Kazlou, PhD candidate at University of Bergen, Norway, and first author of the study.

Decrease in CCS failure rate required

The study highlights the need to expand the number of CCS projects that realise this technology and cut failure rates to ensure the technology "takes-off" in this decade. Today, the development of CCS is driven by policies like the EU Net-Zero Industry Act and the Inflation Reduction Act in the US. In fact, if all of today's plans are realised, by 2030, CCS capacity would be eight times what it is today.

"Even though there are ambitious plans for CCS, there are big doubts about whether these are feasible. About 15 years ago, during another wave of interest in CCS, planned projects failed at a rate of almost 90 percent. If historic failure rates continue, capacity in 2030 will be at most twice what it is today which would be insufficient for climate targets," says Tsimafei Kazlou.

A promising technology with barriers to overcome

Like most technologies, CCS grows non-linearly and there are examples of other technologies to learn from. Even if CCS "takes-off" by 2030, the challenges won't stop. In the following decade it would need to grow as fast as wind power did in the early 2000's to keep up with carbon dioxide reductions required for limiting the global temperature rise to 2°C by 2100. Then starting in the 2040s, CCS needs to match the peak growth that nuclear energy experienced in the 1970s and 1980s.

"The good news is that if CCS can grow as fast as other low-carbon technologies have, the 2°C target would be within reach (on tiptoes). The bad news, 1.5°C would likely still be out of reach," says Jessica Jewell.

The authors say their analysis underlines the need for strong policy support for CCS combined with a rapid expansion of other decarbonisation technologies for climate targets.

"Rapid deployment of CCS needs strong support schemes to make CCS projects financially viable. At the same time, our results show that since we can only count on CCS to deliver 600 Gt of CO2 captured and stored over the 21^st century, other low-carbon technologies like solar and wind power need to expand even faster," says Aleh Cherp, Professor at Central European University in Austria.