The Science Museum’s new climate change exhibition, Our Future Planet, could prove to be one of the most important it has ever created, as well as one of the most controversial.
The exhibition, for which I was an adviser, focuses on natural and technological ways of removing carbon dioxide, the main greenhouse gas that is driving the rise in global temperature and climate change, from industrial emissions and from the atmosphere.
The world faces an urgent task to rapidly reduce greenhouse gas emissions effectively to zero as soon as possible to stop climate change. This will mean a fundamental shift away from fossil fuels as our primary source of energy, and we will have to make this transformation while striving to make people’s lives better around the world.
The level of carbon dioxide in the atmosphere has been increasing since the Industrial Revolution, mainly due to our burning of fossil fuels: coal, oil and natural gas. The current concentration of carbon dioxide is about 415 parts per million (414.63 ppm on 4 May 2021), about 48 per cent higher than its pre-industrial level of 280 parts per million.
This level of carbon dioxide was last experienced on Earth about 3 million years ago, during the Pliocene Epoch, when the polar ice caps were much smaller and global sea levels were 10 to 20 metres higher than today.
Modern human beings as a species have never experienced such a world, and our civilisation has only developed in the 10,000 years since the end of the last Ice Age.
Even at the current level of carbon dioxide, the climate is clearly changing. Global mean surface temperature has already increased by more than 1˚C, glaciers, sea ice and land-based ice sheets are disappearing, sea levels are rising, and the frequency and intensity of many extreme weather events is growing around the world.
Countries have responded to this profound threat by starting to limit and cut their emissions of carbon dioxide and other greenhouse gases.
In 2015, countries finalised the Paris Agreement, which commits them to “holding the increase in the global average temperature to well below 2°C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5°C above pre-industrial levels”.
In 2018, the Intergovernmental Panel on Climate Change published a special report on Global Warming of 1.5˚C, warning of much worse impacts if temperature rises higher.
It pointed out that climate models indicate that in order to have a reasonable chance of avoiding warming of more than 1.5˚C, global emissions of carbon dioxide will not only have to be reduced effectively to zero (net zero) by 2050, but will have to reach negative levels in the second half of this century.
How could we reduce our emissions to net zero or below? “>We must reduce all of current emissions across all sectors as much as possible. This is likely to mean generating all of our electricity from zero-carbon sources, such as wind, solar and nuclear, and then electrifying most of the rest of our economy, such as heating and land transport.” We may be able to deal with the challenge of intermittent supply from renewable sources by managing demand better and through electricity storage.
However, we may also still need some power plants that run on natural gas to supply electricity at critical times. To be consistent with the aim of cutting emissions as much as possible, these plants would need to be equipped with carbon capture, utilisation and storage (CCUS) technology which extracts the carbon dioxide that results from the burning fossil fuels and allows it to be used in products, such as composites, or stored underground instead of released into the air.
One of the best places to store the carbon dioxide may be in disused oil and gas reservoirs, such as those in the North Sea. Oil companies already inject carbon dioxide into wells as a way of maximising the extraction of oil.
In some sectors, it might be difficult to prevent the release of all carbon dioxide from industrial processes. For instance, it might not be possible to replace the use of coking coal in steel-making, or the limestone in cement manufacture. We may not be able to eliminate all the methane, an even more powerful greenhouse gas than carbon dioxide, released by cows and other livestock.
In this case we will still be allowing some residual amounts of greenhouse gases to escape, but to reach net zero emissions and stop global warming we will need to balance these by removing equivalent amounts from the atmosphere. We could do this by planting more trees and other vegetation. Or we could use machines to artificially extract carbon dioxide from the atmosphere and then use or store it. Or we could grow the vegetation and burn it for electricity, known as bioenergy, and store the carbon dioxide produced.
Although these methods have all been proven in concept, we do not yet know whether these natural and technological methods could be scaled up to make a significant impact. For instance, scientists have pointed out that there is a limit to how much land is available for planting trees and other vegetation.
According to the Global Carbon Capture and Storage Institute, there were 26 commercial CCUS facilities worldwide operating in 2020, capable of permanently removing a total of 40 million tonnes of carbon dioxide every year. That is equivalent to less than 1 per cent of annual global emissions of greenhouse gases – human activities in 2019 resulted in the equivalent of 59.1 billion tonnes of carbon dioxide being released into the atmosphere.
The independent experts on the Climate Change Committee describes carbon capture and storage as “a necessity not an option” if the UK is to reach its statutory target of reducing its annual emissions of greenhouse gases to net zero by 2050. It has also concluded that the UK will have to reduce the amount of land available for livestock to create more forested areas that increase removal of carbon dioxide from the atmosphere.
Overall, there are still large uncertainties about how much carbon dioxide we could feasibly capture and store, but also serious doubts about whether we could avoid dangerous climate change without it. Given its potentially critical role over the coming years, the museum’s exhibition is a timely and excellent contributor to promoting public awareness and engagement about this issue.
However, some well-meaning climate campaigners have attacked the museum for creating the exhibition, arguing that the prospect of deploying CCUS in the future removes the imperative to reduce emissions now. That is certainly a risk, but on the other hand we might not be able to avoid dangerous climate change if we do not develop the technology that allows us to achieve negative emissions.
Others have criticised the museum for accepting major sponsorship for the exhibition from the oil company Shell alongside UK Research and Innovation. Some who have not yet visited the exhibition have already declared it to be ‘greenwash’ designed to cover up the company’s role in generating greenhouse gas emissions. However, I know firsthand as an adviser on the exhibition that the company was not involved in its content and design.
I agree that the oil industry should be held to account for past and present attempts to prevent and delay action against climate change. But I also believe that we are more likely to make a rapid and orderly transition to a zero-carbon economy if oil companies play a genuinely committed and active role in reaching that objective. I put these points to Maarten Wetselaar, the Integrated Gas, Renewables and Energy Solutions Director at Shell, during a podcast for the Energy Institute last year. Most of his responses were encouraging.
Shell has recently committed to achieving net-zero emissions by 2050, and has received the support of some its investors, such as the Church of England Pensions Board. However, some of its other investors, such as the Local Authority Pension Fund Forum, have complained that Shell’s plans do not go far enough.
For its part, the Science Museum assesses sponsors using the freely accessible analytical tools developed by the Grantham Research Institute on Climate Change and the Environment for the Transition Pathway Initiative, which was developed to help asset owners to gauge companies’ preparedness for the transition to a low-carbon economy. The Science Museum Group Sustainability Policy commits it to “assessing prospective and current partners using the independent Transition Pathway Initiative (TPI) tool and encouraging them to work towards level three or better on the TPI”.
While some climate activists will be unhappy about Shell’s sponsorship, ‘Our Future Planet’ is an important exhibition which I hope everybody will visit so that they can make up their own minds about the benefits and risks of CCUS.