Carbon Sequestration Technologies: CCUS Methods

In January 2021, Elon Musk tweeted that he would donate USD $100 million towards a prize for the best carbon sequestration technology.¹ The announcement by Tesla’s co-founder made headlines around the world. Furthermore, it also illustrated a growing interest in carbon capture and sequestration. This is the process of removing carbon dioxide from the air and storing it.

One of these methods, carbon capture, utilisation and storage (CCUS), has been identified as an “important emissions reduction technology” by the International Energy Agency.² 

Why do we need carbon sequestration?

Carbon capture and sequestration technologies are required to avoid a climate change crisis. Scientists say that it is not enough to decarbonise the world economy. It is also not enough to prevent pumping over 36 billion tonnes of CO2 into the air every year.³ Decarbonisation would stop adding to a mounting crisis, but it would not reduce high levels of CO2 already in the air.⁴

Trees are currently the cheapest and most effective tool we have to sequester carbon. Plants and trees continually absorb carbon dioxide through their cells, and through photosynthesis, they turn it into energy and oxygen.⁵

This is known as a natural form of carbon sequestration. There are various other methods for carbon sequestration too.⁶

What are the methods of carbon sequestration?

There are two broad categories for carbon capture and sequestration, natural and technological. First, there are natural methods, including planting trees, improved plants and soil management and creating new ecosystems. Also, there are technological methods. These include carbon capture, storage and utilisation (CCUS) technology.⁷

Trees are currently the cheapest method because they require little effort and can absorb up to 48 pounds of carbon per year and over a ton during their lifetimes. Plus, they keep the soil healthy.⁸ 

But, scientists are also looking into new technologies that could do the same task much quicker and perhaps cheaper too. This is why Elon Musk’s donation and prize made big news. While it is vital that we drastically cut carbon emissions and invest in natural carbon sequestration, scientists say that it might be too slow to stop climate change.⁹

In fact, some scientists, economists and engineers are trying to find ways to use carbon dioxide for products. That would help with removing and storing carbon while offsetting the cost of that carbon removal. Unsurprisingly, being able to make money from reusing CO2 also gives companies an incentive to invest in better methods to capture it.¹⁰

What are two ways to increase carbon capture?

Planting new trees

Afforestation and improving the soil are the two quickest and cheapest ways to remove CO2 from the air. What’s more, countries receive credits for implementing these practices as part of the Kyoto Protocol.¹¹‌

Carbon sequestration via the soil

This involves reducing tilling, planting longer-rooted crops and incorporating organic materials. These methods absorb carbon into the soil and stay there.¹²

Whether or not Elon Musk has the right intentions, he kickstarted a much-needed debate on carbon removal and sequestration.

1. Twitter. (n.d.). https://twitter.com/elonmusk/status/1352392678177034242. [online] Available at: https://twitter.com/elonmusk/status/1352392678177034242 [Accessed 16 Mar. 2021].
2. IEA. (n.d.). Carbon capture, utilisation and storage – Fuels & Technologies. [online] Available at: https://www.iea.org/fuels-and-technologies/carbon-capture-utilisation-and-storage.
3. Ritchie, H. and Roser, M. (2017). CO2 emissions. [online] Our World in Data. Available at: https://ourworldindata.org/co2-emissions.
4. Grantham Research Institute on climate change and the environment. (n.d.). What is “decarbonisation” of the power sector? Why do we need to decarbonise the power sector in the UK? [online] Available at: https://www.lse.ac.uk/granthaminstitute/explainers/what-is-decarbonisation-of-the-power-sector-why-do-we-need-to-decarbonise-the-power-sector-in-the-uk/.
5. BBC (2019). What is photosynthesis? [online] BBC Bitesize. Available at: https://www.bbc.co.uk/bitesize/topics/zvrrd2p/articles/zn4sv9q.
6. Usgs.gov. (2017). What is carbon sequestration? [online] Available at: https://www.usgs.gov/faqs/what-carbon-sequestration?qt-news_science_products=0#qt-news_science_products.
7. Usgs.gov. (2017). What is carbon sequestration? [online] Available at: https://www.usgs.gov/faqs/what-carbon-sequestration?qt-news_science_products=0#qt-news_science_products.
8. Usda.gov. (2017). The Power of One Tree – The Very Air We Breathe. [online] Available at: https://www.usda.gov/media/blog/2015/03/17/power-one-tree-very-air-we-breathe.
9. Roberts, D. (2019). Climate change: pulling CO2 out of the air could be a trillion-dollar business. [online] Vox. Available at: https://www.vox.com/energy-and-environment/2019/9/4/20829431/climate-change-carbon-capture-utilization-sequestration-ccu-ccs.
10. Energy Post. (2019). 10 Carbon Capture methods compared: costs, scalability, permanence, cleanness. [online] Available at: https://energypost.eu/10-carbon-capture-methods-compared-costs-scalability-permanence-cleanness/.
11. Noelle Eckley Selin (2019). carbon sequestration | Definition, Methods, & Climate Change. In: Encyclopædia Britannica. [online] Available at: https://www.britannica.com/technology/carbon-sequestration.
12. Ensia (2017). 8 Ways to Sequester Carbon to Avoid Climate Catastrophe. [online] EcoWatch. Available at: https://www.ecowatch.com/carbon-sequestration-2461971411.html.