How do we know what is feasible for a technology that barely exists?

Climate change mitigation for meeting the Paris Agreement requires large-scale deployment of carbon capture and storage (CCS) technologies, as they can reduce CO2 emissions of carbon-intensive industries and result in carbon removal from the atmosphere when coupled with bioenergy or direct air.

Today, the installed capacity of CCS is far from being meaningful for the climate, yet the policy support has been steadily increasing in recent years, most prominently in the Inflation Reduction Act in the US and the EU Net-Zero Industry Act. As a result of this increasing policy support, the capacity of CCS projects in development is currently at its historical peak, and if all of them are realised, operational CCS capacity will increase 8-fold by 2030. However, the feasibility of a rapid, large-scale, and long-term uptake of these technologies has been heavily debated for more than a decade.

To understand whether CCS can expand fast enough for the Paris Agreement target, an international research group led by the University of Bergen (Norway) developed a method for projecting CCS deployment using historical analogues of policy-driven technologies. The method projects feasible technology deployment across three phases of technology lifecycle: formative phase with erratic growth caused by technology and policy learning, acceleration phase with quasi-exponential growth driven by increased returns, and stable growth phase when the technology reaches maximum growth but is no longer accelerating due to countervailing forces.

Having applied this method to CCS, the researchers found that major efforts (yet in-line with historical evidence) would be required to deploy CCS early and fast enough for the 2°C target, but even such boost would be unlikely to bring the technology to a 1.5°C-compatible pace based on the climate change mitigation pathways in the recent Intergovernmental Panel on Climate Change Sixth Assessment report.

The full study and research briefing are published in Nature Climate Change.

Despite the increase of planned capacity, a decrease of project failure rates is required

Whereas it is acknowledged by the IPCC that meeting the Paris Agreement is likely to require a gigaton-scale global CCS deployment, the operational CCS capacity today is only 0.04 Gt/yr. Understanding whether and how fast this gap can be reduced in the near-term requires more insight into the current status of this emerging technology. Thus, the authors document announced project plans for CCS and find that current (2022) plans, if realised, will result in an 8-fold increase of operational CCS capacity by 2030. But how feasible would such increase be given the historical evidence?

Tsimafei Kazlou, PhD Candidate at the Centre for Climate and Energy Transformation at the University of Bergen and the lead author of the article, describes the thought process behind the analysis of near-term feasibility of CCS deployment:

“Whereas the planned CCS capacity for 2030 looks very promising, we show that it looked as promising in 2010. Back then, 88% of these plans failed. Therefore, in understanding the feasible near-term deployment of CCS, we focused on project plans and their failure rates.”

It was found that with the historical failure rate of CCS projects, today’s plans would result in the operational capacity of 0.07 Gt/yr by 2030 – far below what is envisioned by the Paris-compatible mitigation pathways in the IPCC AR6 report (Figure 2), leaving the gap between feasible deployment and climate targets wide open.

However, to account for technology and policy learning that took place since the 2010’s, it is important to consider improvements in planned capacity and its failure rates. To delineate the upper boundary of feasible near-term deployment of CCS, the method introduced in this study relied on the reference case of the early deployment of another capital-intensive policy-driven technology – nuclear power.

It was found that under the most optimistic assumptions, where project plans double by 2025 and their failure rate drops in half to 45% (consistent with the failure rate of early nuclear power plant projects in the US in the 1970’s), 0.37 Gt/yr can be achieved by 2030. This would be in-line with the majority of 2°C but not 1.5°C mitigation pathways (Figure 2).

Tsimafei concludes:

Our work highlights the need to focus on failures in order to understand the prospects for near-term growth of emerging technologies.” 

Medium- and long-term pace of CCS for meeting climate targets

The study continues with the analysis of feasible CCS deployment trajectories in the medium- (2030-2040) and long-term (2040-2100) using reference cases of capital-intensive technologies – solar, wind, and nuclear power.

After the formative phase, technologies ‘takes off’ and enter the acceleration phase where they start growing quasi-exponentially. The study finds that even if CCS manages to do so by 2030, it would need to accelerate as fast as wind power did in the early 2000’s to stay on track with 2°C-compatible mitigation pathways. Overall, only 10% of 1.5°C- and 44% of 2°C-compatible pathways are in-line with the upper boundaries for feasible CCS deployment in the formative phase (2022-2030) and acceleration rates (2030-2040) derived from reference cases of solar and nuclear power (Figure 3, “Feasible by 2040”).

The share of mitigation pathways with feasible CCS deployment further decreases in the stable growth phase after 2040, where only about a quarter of mitigation pathways envisages CCS expansion in-line with the fastest reference case – nuclear power expansion in the 1970s-80s.

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, Associate Professor at the University of Bergen (Norway) and Chalmers University of Technology (Sweden) and the corresponding author of the study.

Feasible deployment of CCS throughout the century

Taken together, only 10% of climate mitigation pathways are in-line with the three upper bounds of feasible deployment in each phase (4% of 1.5°C and 14% of 2°C), and these pathways depict <600 GtCO2 captured by the end of the century (Figure 3).

Jessica Jewell reflects on the relevance of this finding for the research community:

If we can only count on CCS to deliver 600 Gt of CO2 captured and stored over the 21st century, other emerging technologies such as offshore wind and hydrogen production would need to scale up even faster. We plan to utilise our new method with these technologies and hope that this and other findings on the feasibility of climate solutions will be tested in a new generation of climate mitigation pathways, especially in light of the next IPCC assessment cycle. Eventually, this would enable more accurate estimation of the remaining carbon budgets.”

The study involved the University of Bergen, Chalmers University of Technology, Lund University, Central European University, and the International Institute for Applied Systems Analysis with support from ERC, European Commission, and Mistra Foundation.