What is carbon capture and storage – and how can it help tackle the climate crisis?

This article was first published in August 2023 and updated in December 2023.

We need to reduce human-produced CO2 emissions to zero if we are to tackle the climate emergency. But scientists question whether we can stop emissions fast enough. So the race is on to find new ways to remove carbon from our atmosphere and store it safely.

In March 2023, UN Secretary-General Antonio Guterres urged wealthy nations to pool their resources and use “proven and affordable technologies” to achieve zero carbon by 2050.

Among the technologies that Guterres mentioned are carbon capture and storage (CCS), a solution the Intergovernmental Panel on Climate Change (IPCC) says is essential to reaching net zero.

“All available studies require at least some kind of carbon dioxide removal to reach net zero; that is, there are no studies where absolute zero or even CO2 emissions are reached by deep emissions reductions alone,” the IPCC said in a report published in 2022.

CCS projects currently store nearly 45 million tons of CO2 every year - around the equivalent of the emissions created by 10 million passenger cars.

Here's how this process works, its advantages and disadvantages, and why it's important.

Carbon capture and storage is, according to the MIT Climate Portal, a "collection of technologies that can combat climate change by reducing carbon dioxide". This process captures fossil-generated CO2 before it's released into the atmosphere. The CO2 is compressed until it becomes a liquid-like substance that is channeled to a storage site, typically through a pipeline. Most captured CO2 is currently injected deep beneath the ground.

According to MIT, such a process forms a “closed loop” in which carbon is extracted from the ground as fossil fuel and later returned underground as CO2.

But not all carbon capture involves taking CO2 directly from industrial waste gases.

Bioenergy: Plants naturally capture and store carbon dioxide from the atmosphere. When plant material, known as biomass, is burned in a power plant and the CO2 emitted is captured and stored, it creates what scientists call 'negative emissions'.

Seaweed: In Ireland, Carbon Kapture is using seaweed fertilizer to capture carbon and return it to the ground.

The company aims to plant a million metres of rope-grown seaweed by the end of 2024 which will play a key role in removing carbon from seawater. The seaweed will then be heated in a similar process to charcoal-making to produce biochar fertilizer.

“We want to create a circular ecology business model, effectively using nature to help nature to bring back some balance to the imbalance of climate change,” said co-founder Howard Gunstock in an interview with the Forum for the Annual Meeting of the New Champions.

Gunstock says seaweed is “one of nature’s most effective ways of absorbing CO2”, as seaweed captures carbon 30 times faster than trees. By converting it into fertilizer, the captured carbon is then stored safely away in the soil.

As well as Ireland, where they are working with an established shellfish farm to grow seaweed, Carbon Kapture say they are in discussions with partners about similar projects in the UK, Singapore, Newfoundland and the Seychelles.

The UK recently announced a $20 million project to develop systems to capture carbon from energy-intensive industries and transport it by ship or pipeline to offshore storage under the seabed in empty underground oil and gas reservoirs.

Find out more about Creative Instinct and the Global CCS Institute on LinkedIn.

The first stage of the project is expected to store 5 million tonnes of CO2 a year, although the UK alone needs to capture and store 50 million tonnes a year to achieve net zero by 2050, according to official figures.

Globally, the IPCC says between 100 million to a billion tonnes of CO2 will need to be captured and stored over the rest of the current century to limit the rise in global temperatures to 1.5C.

But does CCS really help the transition to net zero? Many critics argue that it’s more expensive than simply switching to renewable energy sources. A report published in 2022 said that underperforming carbon capture projects outnumber successful projects globally.

The Institute for Energy Economics and Financial Analysis said that the majority of CCS projects were actually designed to help extract more fossil fuels by being injected into oil fields to push more oil and gas out of the ground.

Scaling up carbon capture will be expensive. The Tony Blair Institute for Global Change estimates that to build the 70-100 new industrial carbon capture plants needed to hit the IEA’s targets will cost between $665bn and $1280bn annually.

Although large industrial companies could be capable of funding capture projects for clusters of factories, the institute says governments will have to play a leading role. Innovative financing will be needed using instruments like green bonds.

The Global CCS Institute, a think tank that champions the use of carbon capture, says that there are already 30 schemes running around the world with 11 more being built and 153 at the development stage.

“Without CCS, reaching our shared climate goals is practically impossible,” said the Institute’s CEO, Jarad Daniels. “The last few years have been marked by growing ambition from countries and companies alike. That ambition must now translate to urgent, broad and large-scale action if we are to maintain a liveable climate.”

This is a view very much shared by the First Movers Coalition (FMC), a global coalition of companies helping to decarbonize the “hard-to-abate” industrial sectors like shipping, trucking, aviation, steel and cement and concrete.

FMC members have pledged over $15 billion in purchasing commitments for clean technologies such as CCS. By committing to purchase these innovative clean technologies and energy sources, sometimes even at a higher price, members send a powerful signal to producers to increase investment and innovation in these areas, eliminating some of the risk for producers in shifting to greener methods.