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What is carbon capture and how does it fight climate change? What is carbon capture and how does it fight climate change?
(about 1 month later)
Carbon capture and storage infrastructure is designed to prevent carbon dioxide (CO2) from industrial processes and power stations being released into the atmosphere. The future of fossil fuels - particularly whether to agree to phasing out coal, oil and gas - is arguably the key issue of the COP28 climate summit in Dubai.
Currently the technology is seen as expensive but it should in theory enable fossil fuels to be used without making global warming worse. Any agreement is likely to rely on ambitious measures to capture and remove carbon dioxide (CO2) - the main gas responsible for global warming.
New UK plan to reach net zero goal faces criticism Techniques range from capturing CO2 before it is released at power stations and storing it deep underground, to using trees or machines to suck CO2 directly out of the air.
Here's a quick guide to the different types of carbon capture and removal, why they are needed, and their limitations.
What is carbon capture and storage and how does it work?
Carbon capture and storage facilities aim to prevent CO2 produced from industrial processes and power stations from being released into the atmosphere.
Most of the CO2 from burning fossil fuels is captured, transported, and then stored deep underground.
The UK government says the North Sea is an ideal place to store captured carbon, with plenty of old empty oil and gas reservoirs
The UK has announced several carbon capture projects as part of its pledge to capture and store 20-30 million tonnes of CO2 a year by 2030.
Is the UK on track to meet its climate targets?Is the UK on track to meet its climate targets?
How does carbon capture and storage work? The European Union aims to have capacity to capture and store 50 million tonnes a year by 2030, while the United States has also boosted funding.
Burning fossil fuels like oil, gas and coal to generate electricity emits CO2, which is the main driver of climate change. What is carbon dioxide removal?
The carbon capture process stops most of the CO2 produced from being released, and either re-uses it or stores it underground. Carbon dioxide removal is where CO2 already in the air is taken out and stored.
The British government says the North Sea is an ideal place to store CO2. It has plenty of old empty oil and gas reservoirs, and also permeable rocks known as saline aquifers. There are two main approaches.
Why are carbon capture power plants needed? Firstly, humans can try to increase the CO2 taken up by the natural world. For example, one global initiative aims to conserve, restore and plant one trillion trees worldwide by 2030.
Carbon capture power plants are part of the government's commitment to remove carbon from UK electricity production by 2035. It hopes to build at least one by the mid 2020s, although that deadline now looks improbable. This tree seedling was planted by French President Emmanuel Macron, as part of his country's scheme to replant one billion trees by 2030
There has been a big expansion in renewable energy in the last decade, in particular the use of offshore wind, but the unresolved question is how to keep the lights on when the wind isn't blowing. The land and ocean take up more than half the CO2 that humans emit anyway, so carbon removal refers to the extra CO2 that is taken up due to deliberate action by people.
Carbon capture power stations are seen as part of the solution, along with the increased use of nuclear energy, and other rapidly-evolving technologies such as hydrogen. Secondly, there are "novel" human-designed methods to take CO2 out of the atmosphere, although these are at very early stages.
These include machines to directly capture CO2 from the air, or processes involving growing plants, burning them or converting them into fuels, and capturing and storing their emissions. Novel methods the BBC has looked at include a massive seaweed farm in the South Atlantic Ocean and a process known as enhanced rock weathering.
All of the different carbon removal methods are "negative emissions" technologies, because they take CO2 out of the atmosphere - unlike carbon capture, which simply reduces the amount of CO2 being released.
Why are carbon capture and carbon dioxide removal needed?
To avoid the most dangerous impacts of climate change, around 200 countries agreed to try to limit long-term warming to 1.5C above pre-industrial levels - before humans started burning large amounts of fossil fuels.
But human activities are still emitting record levels of CO2. At the current rate, this could take the world past the 1.5C mark by 2030.
And in the coming decades people will continue to rely on activities that produce CO2, including fossil fuels for energy, even though this should fall as renewables like solar power grow. There is also no realistic way of eliminating all emissions from some sectors, like agriculture and aviation, without carbon removal.
This means the world will almost certainly need some carbon capture and removal in order to limit warming to 1.5C, according to the UN, even if governments manage to make steep cuts to emissions.
What is net zero?
What is the problem with carbon capture and removal?
Neither approach is taking place at anywhere near the scale required to balance CO2 emissions from human activities, which exceeded 40 billion tonnes in 2022.
In comparison, carbon capture and storage currently only captures around 45 million tonnes a year. Carbon dioxide removal by artificial methods takes up even less - around 2 million tonnes a year. Both remain very expensive.
Based on projections of oil and gas use under current policies, the world would need these methods to capture and remove an "implausible" 32 billion tonnes of CO2 a year by 2050, according to the International Energy Agency.
This Orca plant in Iceland is the direct air capture and storage facility, with the potential to remove 4,000 tonnes of CO2 from the air per year
Carbon dioxide removal by enhancing natural sources - like tree planting - removes an estimated 2 billion tonnes a year. But even this is outweighed by the carbon emitted from the damage to the natural world, like continued deforestation, and there are limits to how much carbon trees can take up.
For these reasons, carbon capture and removal cannot be used as an excuse to avoid rapidly reduce fossil fuel production and use, the International Energy Agency and other bodies stress.
In fact, many campaigners accuse such schemes of "greenwashing" - where governments and businesses promote their climate credentials without making the real changes needed.
More on the COP28 climate summit
What is COP28 and why is it so important?
A really simple guide to climate changeA really simple guide to climate change
Is the UK on track to meet its climate targets? Five reasons for optimism on climate
What has the government committed to? How is my country doing on tackling climate change?
In March the government agreed to go ahead with funding three carbon capture facilities near Redcar on Teesside. One will capture carbon from a gas-fired power station and the two others from hydrogen production. All would connect to a pipeline that transports the captured CO2 under the North Sea for storage. Five projects in north west England and North Wales are also in the final stages of development with the CO2 there being stored under the River Mersey. Five climate change solutions under the spotlight at COP28
The government is supporting the development of carbon capture clusters, hubs where different industrial processes can plug into the same CO2 pipes and storage systems. The two most advanced clusters are the East Coast Cluster (Teeside/Humber) and Hynet (North-west England and North Wales).
In July two new clusters Viking (Humber) and Acorn (north east Scotland) were chosen as the UK's third and fourth carbon capture and storage clusters.
How much CO2 will the carbon capture plants remove?
In 2021, the UK emitted 425m tonnes of CO2. That's fallen by almost 50% since 1990.
The amount being captured at these proposed power stations is very small by comparison.
None of the proposed carbon capture plants claims to capture more than 2m tonnes a year.
The government has set a target to capture between 20-30m tonnes of CO2 a year by 2030. That could involve other industrial processes as well as power generation.
How much will carbon capture and storage cost?
Capturing the carbon dioxide from industrial processes and then storing it underground requires infrastructure. That means the processes will be more expensive than projects where the CO2 is simply emitted into the atmosphere.
The basic technology has been around for decades. It's mainly been used in industries where captured CO2 can be reused, for example to force out oil and gas from underground reserves.
There are no such plans to use the CO2 from new power stations.
The cost of a new gas power station, providing electricity for nearly a million homes, is around £350m.
Catherine Raw of energy company SSE told the BBC that building a similar sized gas power station with carbon capture would roughly double the cost.
The hope is that the price might fall over time in same way that the coast of renewable energy has plummeted in the last decade.
There are those who see carbon capture as too expensive and believe the money would be better spent on renewables and power storage (like batteries).
"These power stations look like another excuse for the government to show preference to their friends in the oil and gas industry, making energy more expensive to everyone else's disadvantage," says Dr Doug Parr of campaign group Greenpeace UK.
Do other countries have carbon capture?
In September 2022 there were just 30 carbon capture facilities in the world, according to a report from the Global CCS Institute.
Almost all of these are attached to industrial plants carrying out activities such as natural gas processing or fertiliser production.
Once built, it is hoped other industries would use the UK power station's pipeline to store CO2 under the North Sea.
Built in 2014, the Boundary Dam power station removes up to 90% of the CO2 it generates
The only carbon capture power station currently operating is a coal-fired plant at Boundary Dam in western Canada.
However, several carbon capture gas power stations similar to those proposed in the UK are in development, mostly in the US.
Related TopicsRelated Topics
Carbon capture and storageCarbon capture and storage
Greenhouse gas emissionsGreenhouse gas emissions
Energy industryEnergy industry
COP28
ClimateClimate
Renewable energyRenewable energy
Net zeroNet zero