Can carbon-capture machines save us from climate catastrophe?

We need to stop pumping carbon emissions into the atmosphere  (PA Wire)
We need to stop pumping carbon emissions into the atmosphere (PA Wire)

The United Nations Climate Change Conference, known as COP27, is just around the corner, and world leaders will once again convene to address our generation’s biggest global issue: climate change.

Over the past few years, as the public has awakened to the reality of climate change, companies, scientists, and governments have turned their attention to developing solutions to help the world achieve net zero as soon as possible.

One area where this hope often burns brightest is carbon capture. Hailed by some as an indispensable tool in the fight against climate change, while reviled by others as nothing more than greenwashing, nonetheless the idea of taking CO2 from the air and putting it back into the ground has gained more attention – and money – in recent years.

So what exactly is it, and could it really help us tackle climate change?

What is carbon-capture technology?

Carbon capture aims to tackle emissions from fossil-fuel combustion by trapping and separating the CO2 from other gases, before putting it back into the ground.

Carbon dioxide is absorbed or otherwise collected from the air or directly from facilities producing things like cement and steel.

It is then stored underground, and sometimes underwater, where it can remain for decades or even centuries when managed properly.

What is the state of current carbon-capture technology?

According to the Global CCS Institute, a thinktank that promotes carbon capture, there are 200 carbon-sequestration projects now in operation or in development around the world.

Barclays, ExxonMobil, and ArcelorMittal are among the companies turning to CO2 sequestration as a way to meet their net-zero goals.

Carbon-capture technology has been used for almost three decades, often to improve oil-extraction rates. But recent tax incentives and rising prices for carbon, in regions like the US and Europe, have reignited the possibility that it may be an economically attractive way to tackle climate change.

Are there other ways to capture carbon from the atmosphere?

Capturing CO2 via complex machines isn’t the only way to sequester gas from our atmosphere. Some entrepreneurs and scientists are exploring much less advanced technology – seaweed.

Kelp is known to absorb large amounts of carbon dioxide as it grows, and often becomes so heavy that it sinks to the bottom of the ocean, where it can remain for decades.

Working off this science, a British businessman has dreamed up a giant seaweed farm as big as Croatia, planted between Africa and South America in the Atlantic ocean. The project would be able to capture up to one gigatonne of carbon per year – a significant dent in the world’s 36 gigatonnes of CO2 released last year.

Other scientists have even toyed with the idea of tweaking seawater’s alkalinity levels to boost its ability to absorb CO2 from the atmosphere. But, so far, marine CO2 capture is still an area that needs much more research.

How does carbon-capture technology fit into the race to net zero by 2050?

The reality is that, for now, carbon-capture projects look set to play only a small part in the world’s race to net zero.

Currently, all carbon-capture projects under development worldwide would only suck away less than one per cent, or 244 million tonnes, of the 36 gigatonnes of carbon dioxide released into the atmosphere last year.

Indeed, consultants McKinsey calculated that carbon-capture projects need to increase 120-fold by 2050 in order for countries to meet their net-zero goals.

That hasn’t stopped countries, and companies, from trying. The UK is planning to store captured carbon under the North Sea, as part of its ambitions to achieve net zero by 2050.

And a joint venture between oil giants Shell, Total, Equinor, and the Norwegian government, named Northern Lights, is aiming to become the world’s biggest carbon-capture project when it is completed in 2024.

The United Nations’ Intergovernmental Panel on Climate Change (IPCC) also noted CO2 capture could be particularly useful for fossil-fuel heavy industries like steel, cement, and natural gas processing, that cannot easily reduce their emissions.

Why carbon capture isn’t enough

So far, most of the world’s carbon-capture projects have focused on enhanced oil recovery, or EOR, where the CO2 extracted from the atmosphere is reinjected into oil fields to help pump more oil out of the ground.

A report from the Institute for Energy Economics and Financial Analysis found that carbon capture from EOR projects made up about 73 per cent of the CO2 captured globally each year.

Effectively, this is taking carbon out of the air to extract fossil fuels that put more carbon back in the air. Not exactly the best way to permanently reduce CO2 in the atmosphere.

Stashing away carbon also comes with significant challenges, from finding suitable sites, to monitoring them for centuries to ensure the CO2 doesn’t leak back into the air.

Critics also say that funneling funds towards carbon-capture tech takes away money from renewables, and doesn’t wean the world off its addiction to fossil fuels. It also doesn’t help that the technology has scarcely made advances in the past 30 years.

To some, carbon capture also looks like a way for oil companies to justify their pumping of the black stuff while cleaning up the mess it causes.

But perhaps Ken Caldeira, senior scientist emeritus at the Carnegie Institution for Science’s Department of Global Ecology, summed it up best when he told the Wall Street Journal: “It’s easier to avoid making the mess in the first place than it is to clean it up afterwards.”