Can carbon capture work?

When it comes to climate change mitigation, few technologies are as controversial as carbon capture and storage (CCS). Most climate scenarios expect the technology to grow extremely fast until 2040 and the fossil fuel industry likes to point to CCS as their preferred way to reduce greenhouse gas emissions. Critics, on the other hand, point to the high failure rate of pilot projects (historically 88% of projects failed to meet their targets) and the slow rollout to brand CCS as little more than wishful thinking that distracts from the effective climate action that could be taken now.

So, I am glad that Tsimafei Kazlou and his colleagues have published a detailed study of the potential rollout of CCS in Nature Climate Change. They emphasise that other low carbon technologies like wind, solar, and nuclear all had high failure rates and slow rollouts in the beginning. But as engineers and businesses climbed the learning curve, failure rates dropped a lot and rollout accelerated faster than anyone anticipated. Indeed, to this day, analysts tend to underestimate the growth of renewables like wind and solar.

To estimate the potential future pathways of CCS development, the researchers applied these lessons to CCS. The charts below are the heart of the note and take some explaining, so let me go through them step by step.

Prospects for CCS deployment to 2030

Source: Kazlou et al. (2024)

The chart on the top left (a) shows the development of operational capacity and planned CCS projects globally. In 2022, operational facilities had a tiny capacity of 0.04Gt/yr of CO2.

The chart on the top right (b) shows where we might be in 2030 under different assumptions for the failure rate of CCS projects that are currently being planned and deployed. Without any failures, capacity would rise to 0.34Gt/yr. Of course, not all these projects are going to be successful, so the chart shows capacity projections under failure rates equal to the historic failure rate, the failure rate of solar and wind, and the one for nuclear power at similar stages of development. Nuclear power had historically a much lower failure rate than wind and solar, so that is plotted as a best-case scenario. In this best case, capacity could reach 0.2GT/yr, still not enough than what is needed under a 2C scenario, let alone a 1.5C Paris scenario.

However, in the chart on the bottom left (c) the other variable that determines CCS rollout is taken into account as well. As more projects come online and the learning curve improves, more and more projects are being planned and funded. If the number of planned projects doubles in the next couple of years, the operational capacity of CCS in 2030 could reach 0.37Gt/yr. And that, as the chart shows, would be more than is needed under most 2C scenarios but still not enough to get on a 1.5C scenario.

In short, CCS can still work, and it can play an important role in keeping global warming within 2C in the long run. In their simulations, CCS technology rollout would be sufficient to reach 2C in 44% of all potential pathways. But it is very unlikely that we will get to the CCS capacity needed to keep global warming within 1.5C. Only a 10% chance in the authors’ simulations.

But then again, we’ll never have Paris anyway. For years now, climate action has been so slow that reaching the Paris climate goals is now virtually impossible as I mentioned here. But if we set our goals to a more realistic target, then CCS can play an important role, as long as we get the failure rate down and the trajectory of CCS rollout roughly follows that of wind, solar, and nuclear power in the past.