Many of the best scientists in the UK working on carbon capture technologies do not believe that they will be developed and increased in time to reach net zero and limit global warming to 1.5C.
Experts speaking at an event at the London Greenhouse Gas Removal Center warned that these techniques, including direct air capture, biofuels, biochar, afforestation and advanced weathering, are not a silver bullet and should only be part of the effort. decarbonization.
The researchers were asked by the organizers of the event whether they believe that the goals of carbon sequestration will be achieved. Of the 114 scientists in the audience, 57% said they were “not confident” that the UK would meet the 2030 targets in the net zero strategy of 5 million tonnes of engineering greenhouse gas removal and 30,000 hectares of annual tree planting. ; 25% said they were quite confident and 11% said there was no chance.
Scientists are taking part in a government-funded £ 70m race to find the best ways to remove greenhouse gases from the atmosphere. These technologies must begin to remove huge amounts of carbon dioxide from the atmosphere by 2030 in the hope that profitable methods can be expanded and ready for the market in two years.
The government seems generally confident that carbon capture methods will be developed fairly quickly. The Ministry of Transport said, for example, that greenhouse gas removal technologies (GGR) would allow the British to take “no-fault flights” by the end of next year, but participants in the program were less optimistic.
But when a press release was issued by the government declaring that these technologies would allow zero net flights by 2023, Prof. Mark Taylor, deputy director of energy innovation at the Department of Business, Energy and Industrial Strategy (BEIS), he seemed skeptical. He told the Guardian: “No, that’s not the case. We need to make people believe that this can work, but maybe that statement is a little cheeky. ”
Gideon Henderson, chief scientist in the Department of Environment, Food and Rural Affairs (Defra), said: “GGR is difficult and expensive. And we cannot afford to see it as a surrogate to compensate for continued emissions in sectors that can be decarbonized. This is not an excuse not to decarbonise, so we still need to reduce emissions. “
So far, the most popular technology based on applications to the program has been direct air capture. This process involves removing carbon from the air, usually with the help of giant fans, and heating to a very high temperature. This carbon can then be stored in geological formations or combined with hydrogen to create synthetic fuels.
While ministers like the idea, program leaders say it may not be the answer because of the energy intensity required and how expensive it is.
Taylor said: “People see it as the biggest market, it’s funded by American companies – it feels like a silver bullet, there are a lot of people who like it. Ministers like it because they think, “Oh, that sounds easy, you can put it on the air and that’s it.” And that’s what gets an investment.
“I am very surprised if this is the best solution. It is very, very expensive. So some of the other technologies may be the winners, but the good thing about our competition is that we choose the best.
The Guardian turned to BEIS for comment.
Greenhouse gas removal methods are being tested with UK funding
Aforestation Henderson said it was GGR’s “poster child” because “everyone seems to love it and it’s nice to have more trees.”
However, he said that trees “are not a panacea” because of the amount of land they need, which is taken away from food production, which then causes tensions in food security. There is also tension between forests that benefit more from biodiversity but grow more slowly, and forests that grow faster and lock in more carbon earlier.
Soil storage While storing carbon in the soil is a popular method, Henderson says there are concerns about how long carbon can be stored in the soil and how it is measured. If the soil starts to release carbon again shortly after storage, this can cause problems, especially if it is not measured effectively and is not counted in net zero targets.
He explained: “I think that if we see significant financial resources coming in this area to stimulate the storage of carbon in the soil, without being able to measure it, and to be sure of its sustainability, there is a risk of continuing emissions from storage, which are not constant or well enough measured. “
Advanced weathering The release of small rock particles into the sea to trigger chemical reactions that block carbon in the ocean is potentially a very exciting technology, but at an earlier stage than many other carbon capture methods. It has interesting potential because the ocean stores carbon in higher concentrations than in the air. There is even hope that it can help reverse the acidification of the ocean. However, there are also fears that the process could upset the delicate balance of the oceans.
Direct air capture The idea of a machine that can suck carbon dioxide out of the atmosphere and drive it permanently into rocks is very attractive, and perhaps not surprisingly, it is the most popular technology for scientists trying to decide. this problem.
But at the moment this is a very energy-intensive process. Taylor explained: “We need to use energy to extract CO2, the net flow of CO2 from solids, so what we are looking for integration can reduce the cost of DAC and in particular reduce the cost of extracting CO2 and energy costs for CO2 extraction. Because at the moment it makes no sense to capture CO2 from the air and then use natural gas to conduct a thermal process to extract a clean stream of CO2.
Biofuels While Henderson pointed out that this is carbon sequestration, which is already happening on a large scale in the UK and could be a “really powerful form of greenhouse gas removal”, there are concerns about biodiversity and land use pressures. This is because growing crops often creates a monoculture and this land is taken away from food production.
BiocharBiochar is a stable, long-lasting, carbon-like product produced by heating biomass in the absence of oxygen. It is rich in carbon and can be applied to the ground to capture CO2 in soils for extended periods of time. This can be relatively easy and inexpensive, but there are concerns about how long carbon will be stored and whether it will have negative effects on the soil.
Add Comment