Tackling climate change may bring unexpected benefits, London’s Science Museum will reveal next month. A special exhibition on carbon capture, the fledgling technology of extracting greenhouse gases from the atmosphere and emissions from factories, will display bottles of vodka, tubes of toothpaste, pens and yoga mats made from carbon drawn out of thin air.
In addition, the exhibition – Our Future Planet – will showcase prototypes of the gas-harvesting machines that can provide this carbon. They include the Lackner artificial tree which mirrors the actions of living plants by breathing in carbon dioxide and exhaling oxygen. This Heath Robinson-like device – made up of dangling panels of carbon-absorbing material – was built by Klaus Lackner at Arizona State University and will be the first to be displayed in Britain.
Also featured will be the Swiss Climeworks carbon extractor system and a carbon capture device developed at Aberdeen University. All can remove carbon from air, to be used for alcohol or products such as Open Air toothpaste. The taste of tomorrow may be flavoured with air-captured carbon. “These objects highlight the importance of research to help protect the planet from the effects of global warming,” added Sophie Waring, curator of the exhibition which opens on 19 May.
But Our Future Planet also makes it clear that even moderately large arrays of these devices can currently extract only a few tens of tonnes of carbon a year – compared with the 50 billion tonnes that fossil-fuel burning cars and factors add annually to the atmosphere. “It is a massive problem,” said Bob Ward, policy director at the Grantham Research Institute on Climate Change and the Environment. “We need to remove carbon from the air because it is unlikely that cutting greenhouse gas emissions alone can be achieved quickly enough to prevent global overheating this century.”
“We have to do more than merely halt carbon dioxide getting into the atmosphere. We also need to find ways to remove it after it has been put there. Simply planting trees and plants will not be enough to solve the problem. This exhibition shows just how urgent is the need to develop and deploy these new technologies on a large scale to make a real difference in fighting climate change,” added Ward, an exhibition adviser.
Earth’s climate crisis was recently highlighted by the UK Geological Society which revealed that carbon dioxide is now being added to our atmosphere at a rate “unprecedented in almost the entire geological past” of our planet. Levels may have been higher at times but they have never risen at a rate as rapid as its current increase. “As the climate changes, the planet we live on will experience further changes that will have increasingly drastic effects on human societies,” the society warned.
Last month levels of the gas in the atmosphere reached 417ppm (parts per million) compared with around 280ppm in pre-industrial times. And given that carbon dioxide absorbs solar radiation, this means the gas is increasingly warming the air above us, triggering more extreme weather patterns, water shortages, sea level rises, melting ice caps and crop failures.
In the next few weeks, a series of international climate meetings will be held, including a global summit to be chaired by president Joe Biden. These are being staged in the lead-up to the COP26 climate talks in Glasgow in November. Unlike his predecessor, Biden is committed to tackling global warming and is tipped to announce that the US will introduce tougher measures to bring down its carbon emissions more rapidly. Such a move would have major implications for other countries.
But even if every nation – including China and India – followed suit, the world would still be on a dangerous trajectory, many scientists have warned. Only by actively removing carbon dioxide from the atmosphere to create “negative emissions” will it be possible to keep global warming down to a manageable 1.5 to 2C above pre-industrial levels, they argue. As a result, carbon capture systems need to be developed urgently.
Carbon capture is not without its green critics, however. Some environmentalists believe it is being developed as an alternative to cutting carbon emissions and not as an additional method for moderating global warming. They have also criticised the Science Museum for involving the petrochemical company Shell as a sponsor of the exhibition.
In fact, carbon capture technology has two different roles to play, said geologist Professor Stuart Haszeldine, of Edinburgh University. “Firstly, it can be fitted to gas and coal-burning power stations and factories and then used to hold back the carbon dioxide they would otherwise emit. This can then be liquefied and stored underground, for example in depleted oil fields.
“However, the technology can also be used to recapture carbon dioxide from the air, to extract carbon dioxide that had already been pumped into it. Crucially we need carbon capture and carbon recapture if we are going to mitigate the worst impacts of global warming while at the same time being more efficient in our use of carbon.”
Doing this on an effective scale will be very hard. However, devices like the Lackner tree and the Climeworks extractor offer a promising route, added Haszeldine. “They can be improved upon relatively quickly to make succeeding generations that are cheaper and more efficient.
“It is like the mobile phone. Twenty years ago they were expensive and awkward to use but have been improved upon relentlessly. We might be able to do that for carbon capture machines like the Climeworks and the Lackner devices and could end up with vast arrays of them sucking carbon dioxide out of the atmosphere. Certainly, if we don’t do something like that we will be in real trouble.”
