An innovative project to absorb carbon dioxide from the sea is being tested off the south coast of England. Around 25% of greenhouse gases emitted by human activity are absorbed by the oceans. Seacure is funded by the UK government as part of its research into technologies to combat climate change. There is a broad consensus among climate scientists that the priority is to reduce greenhouse gas emissions, the main cause of global warming. “The aim is to remove carbon dioxide from seawater. The reason for this is that there is a lot of carbon dioxide in seawater, more than there is in the air. Removing it from seawater, rather than the air, is a good start,” said Professor Paul Halloran.
Seawater contains about 150 times more CO2 than air. What makes Seacure interesting is that it is testing whether it could be more efficient to pull the carbon that causes global warming from the sea. The treated water is then returned to the marine environment.
“This step in the process is taking CO2, from the atmosphere, but through the ocean, and bringing it to a stage where it’s clean. When it’s clean, you can compensate for it, you can transport it and ultimately you can store it,” added Paul Halloran. It’s a pipe that snakes under the rocky beach and out into the English Channel, sucking up seawater and bringing it to shore. The project is trying to find out whether removing carbon from water could be a cost-effective way to reduce the amount of CO2 that’s warming the climate. There are already much more advanced carbon capture technologies that remove it directly from the air, but Dr. Paul Halloran, who leads the Seacure project, says using water instead has its advantages.
“This is new technology and we are still gathering the scientific data to make good decisions about this. One of the things we are doing is those environmental impact experiments to make sure that it is environmentally responsible what we are doing,” Professor Halloran continued.
Seacure said the technology had the potential to be scaled up massively to remove 14 billion tonnes of CO2 per year if 1% of the world’s seawater was processed. The team said the process faces challenges, including high energy requirements and costs. The Seacure project is being led by the University of Exeter’s Global Systems Institute, along with the Plymouth Marine Laboratory, Brunel University London and Eliquo Hydrok. The government has allocated £3m in funding for the project, which is seen as vital in the wider drive to achieve net zero emissions and curb global warming.
