Carbon capture: What other countries are doing compared to the UK

Rishi Sunak's announcement of a £20bn carbon capture scheme in a bid to reach net zero emissions by 2050 has been met with scepticism by some.

The project - in North East Scotland and the Humber region - is being hailed by the government as a step towards carbon neutrality, while supporting 50,000 new jobs by 2030 and adding up to £5bn to the economy by 2050.

However, the prime minister's decision to commit to more than 100 new licences for North Sea oil and gas extraction - in practically the same breath - has prompted environmentalists and eco-minded MPs to raise their eyebrows.

Sunak has insisted the pledge is essential to bolstering the country's energy security, in a bid to prevent Vladimir Putin weaponising the supply of energy following Russia's invasion of Ukraine.

Watch: Rishi Sunak defends approving new oil and gas licences in the UK

Nonetheless, one of his party's own MPs, Chris Skidmore, has said the PM is on the "wrong side of history" and on "the wrong side of a future economy that will be founded on renewable and clean industries, and not fossil fuels".

At first glance a large-scale carbon capture project may seem like the perfect antidote, but critics argue the technology still requires much more advancement, and that it could be used as a fig leaf to justify the continuation of fossil fuel use.

Here, Yahoo News explains what carbon capture is, how far ahead the UK is with it compared to other countries, and why people are divided on it.

How far ahead is the UK with carbon capture?

Currently there are no commercial-scale carbon capture operations in the UK, but the government has committed £20bn for the “early deployment” of carbon capture technology over the next two decades.

Earlier this year, energy secretary Grant Shapps said the UK has an advantage of being able to store captured CO2 in giant caverns underneath the North Sea.

But the strategy has been met with scepticism, as previous carbon capture projects have been abandoned over a number of years.

One example was in 2015, when the government withdrew its £1bn support for the technology six months before it was due to be awarded, and just days before COP21.

Read more: Why Rishi Sunak and his private jet are under fire... again

How does the UK compare to other countries?

Worldwide, there are around 40 commercial facilities in operation applying carbon capture, utilisation and storage (CCUS) to industrial processes, fuel transformation and power generation, according to the International Energy Agency (IEA).

However, the intergovernmental organisation says momentum has grown in recent years, with more than 500 projects in various stages of development.

The USA – one the world's biggest CO2 emitters – has extensive expertise in the sector, mainly driven through its well established oil recovery industry, according to Energy Focus.

This process involves injecting captured carbon dioxide back into dwindling oil wells to try and force more oil out of the ground that couldn't otherwise be extracted – a practice which has prompted backlash from environmentalists.

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In 2022 the US announced a string of measures expected to boost CCUS development, including new funding under the 2021 Infrastructure Investment and Jobs Act and favourable CCUS tax credit changes.

Norway is also aiming to become a major player in the carbon capture world with its Northern Lights project, which developers have said will be ready to take CO2 emissions from Europe by 2024.

Australia is home to the world's largest commercial carbon capture and storage plant, Gorgon, located on Barrow Island to the west of the country.

Read more: BBC Climate Editor Justin Rowlatt defends flying to Spain to report on heatwave

However, in May, the project's owners, Chevron, admitted the plant was running at just a third of its planned capacity, raising doubts among critics over the technology's future.

Indonesia finalised its regulatory framework for carbon capture and storage in March, while Japan has chosen seven candidate projects. China has seen three new projects become operational this year.

How does carbon capture work?

Carbon capture and storage involves taking CO2 at the source of the emissions, transporting it and then storing or burying it at a deep, underground location.

One method of doing this is post-combustion, which is used in power plants. It works by using a solvent in a separation tower to absorb flue gas - a mixture of gasses produced from burning fuel.

From there, the CO2 is separated in a recovery chamber at temperatures over 100C and then compressed for easy transportation.

The main advantage of this technology is that it can be easily be retrofitted to existing power plants, according to the UK Carbon Capture and Storage Research Community.

Another method is pre-combustion capture, which works by trapping the carbon dioxide in fossil fuels before they are burned. First, it is partially burned in a "gasifier" to form a synthetic gas.

CO2 can be captured from this relatively pure exhaust stream, the British Geological Survey explains. The process also produces hydrogen, which can be separated and used as fuel.

There is also direct air capture, where technologies are used to extract CO2 directly from the atmosphere at any location, but this is the most expensive method and requires much more energy to carry out.

What about planting trees?

Another much more low-tech way of capturing carbon is by planting trees, which naturally take CO2 from the air and store it in their wood.

However experts from the Massachusetts Institute of Technology (MIT) warn that as humanity has tipped the natural balance of CO2 absorption so much with its emissions, it's impossible to say how many new trees would need to be planted to restore it.

For this reason, it says we should also be putting much more effort into protecting our existing forests, as well as planting new trees.

Why is carbon capture controversial?

Earlier in July, a group of countries warned that technologies used to capture CO2 emissions are no substitute for a drastic cut in fossil fuels.

In a statement, the European Union and 17 countries including Germany, France, Chile, New Zealand and the Marshall Islands said these projects "must not be used to green-light continued fossil fuel expansion".

The announcement, made ahead of November's COP28, will seem all the more relevant given Sunak's pledge to invest in carbon capture and storage while giving the go-ahead to new gas and oil projects.

A 2022 study by the Institute for Energy Economics and Financial Analysis claimed that project developers have "almost always reused the captured carbon for enhanced oil recovery, producing oil and gas and more emissions".

Read more: Rishi Sunak stands by oil drilling expansion as critics warn of climate consequences

It says nearly three-quarters of CO2 captures annual is injected back into oil fields, with just 27% stored underground.

However, many do see this technology as a piece of the puzzle as nations try to achieve the Paris Agreement's goal of keeping global temperatures at less than 2C above pre-industrial levels.

One such voice is the IEA, which argues that as power plants fuelled by coal and gas continue to dominate the global electricity sector – accounting for nearly two thirds of power generation – the world can't afford not to invest in carbon capture and storage.