Climate engineering

The case for technology-based carbon removal

By Oregon Department of Forestry - https://www.flickr.com/photos/oregondepartmentofforestry/16637208254/, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=87685933

165 billion tonnes of carbon will need to be removed from the atmosphere by 2050 in order to limit climate change to 1.5°C, according to the Energy Transitions Commission. That’s equivalent to 10 billion tonnes of carbon each, and every year.

Carbon removal technology is essential if we are to meet net zero targets.

First, nature-based carbon credit projects will have to compete with other demands on the land. The Intergovernmental Panel on Climate Change (IPCC) estimates that land-based carbon removal methods, including afforestation and reforestation could yield a maximum of about 19 billion tonnes of CO2 per year, requiring 1 billion hectares of land. In comparison, 1.5 billion hectares of land are currently devoted to growing crops worldwide (see The 'green lairds': How carbon and natural capital investors are driving demand for land).

Secondly, the crucial distinction between nature and technology based carbon removal offset projects is the degree of permanence and requirement for ongoing monitoring. For example, the benefits of nature based projects accrue over several decades or more and risk being undone due to fire or illegal logging. Technology based removal projects sequester carbon immediately and with much less risk of subsequent release (see Technology-based carbon removal credits crucial if net-zero targets are to be met and and Banking on 'blue carbon': Everything you need to know about carbon credits sourced from the ocean).

Finally, carbon removals are likely to become a feature of regulated compliance schemes. For example, the original “Fit for 55” trajectory for the EU ETS cap implies EU ETS-regulated emissions must hit zero emissions by 2040. Carbon removals - either nature or technology based solutions - will become essential if the EU is to meet its net zero target (see The zero lower bound: What happens when EU ETS emissions approach zero?). Other compliance markets including the UK ETS and many in Asia are also exploring the potential for carbon removal to meet compliance (see Why Asia is pivotal to future carbon market growth).

In short, technology-based removals must scale up, and quickly.