A pioneering project to capture carbon from the sea has officially started operating on England’s south coast, marking a significant step in the global fight against climate change. The project, known as SeaCURE, is being funded by the UK government as part of its commitment to developing new technologies that can help reduce carbon emissions and tackle global warming. Though still in its early stages, SeaCURE is exploring the possibility of capturing carbon from seawater, a method that could play a crucial role in reducing the greenhouse gases that contribute to climate change.
This project is part of a larger global effort to find innovative solutions to mitigate the effects of climate change. While cutting greenhouse gas emissions remains the top priority, many scientists believe that it will also be necessary to capture and remove some of the carbon dioxide (CO2) that has already been released into the atmosphere. The SeaCURE project is one of several initiatives looking at this possibility, and its focus on capturing CO2 from seawater has the potential to be a game-changer.
SeaCURE is a small-scale pilot project designed to test the feasibility of extracting carbon from seawater and returning it to the ocean in a more neutral state. The project is located near the Weymouth Sealife Centre on the southern coast of England, where a pipe system runs under the stony beach and out into the Atlantic Ocean. The aim of the project is to determine whether it is more efficient and cost-effective to remove carbon from the ocean rather than directly from the air.
The project works by processing seawater to remove CO2, then pumping it back into the sea where it can absorb more CO2 from the atmosphere. The team behind SeaCURE hopes that this process could one day be scaled up to remove significant amounts of CO2 from the atmosphere, thereby helping to reduce the harmful effects of climate change.
The process begins with seawater being sucked through a pipe and brought onshore, where it is treated to make it more acidic. This acidity encourages the carbon dissolved in the water to transform into gas, which is then released into the air as CO2. To maximize the contact between the seawater and the air, the water is spread over a large surface area, much like opening a fizzy drink and allowing the bubbles to escape. This step is referred to as the “seawater stripper,” a large stainless steel tank designed to maximize the release of CO2 from the water.
Once the CO2 is separated from the water, it is captured and concentrated using charred coconut husks, which are known for their ability to absorb carbon. The water is then treated with alkali to neutralize the acid and is returned to the sea, where it can once again absorb more carbon from the atmosphere. This cycle continues, contributing, in a small way, to reducing the overall carbon levels in the atmosphere.
Professor Tom Bell from Plymouth Marine Laboratory, who is overseeing the project, explains the process in simple terms. “When you open a fizzy drink it froths, that’s the CO2 coming out,” he says. “What we’re doing is spreading the seawater on a large surface area to help the CO2 come out quickly.”
Seawater is considered an attractive option for carbon capture because it holds far more carbon than the air—about 150 times more, according to Dr. Paul Halloran, the leader of the SeaCURE project. However, there are challenges involved in using seawater for this purpose, primarily the high energy requirements needed to process the water and remove the CO2.
At the current stage, SeaCURE is removing only a small amount of CO2—around 100 metric tonnes per year. This is equivalent to the carbon footprint of approximately 100 transatlantic flights. While this amount is tiny compared to the scale of global emissions, the SeaCURE team believes the technology could be scaled up significantly if proven successful. If just 1% of the world’s ocean surface were processed, it could potentially remove up to 14 billion tonnes of CO2 annually, an enormous contribution to the fight against climate change.
For the project to be viable on a larger scale, it would need to be powered entirely by renewable energy. This could be achieved through solar panels installed in floating structures at sea, making the process both sustainable and energy-efficient.
The SeaCURE project is part of a broader effort by the UK government to explore new technologies that could help tackle climate change. The project has received £3 million in funding from the government and is one of 15 pilot initiatives backed by the UK as part of a push to develop carbon capture and storage technologies.
Energy Minister Kerry McCarthy emphasized the importance of projects like SeaCURE in achieving the UK’s climate goals. “Removing greenhouse gases from the atmosphere is essential in helping us achieve net-zero emissions,” McCarthy said. “Innovative projects like SeaCURE play an important role in creating the green technologies needed to make this happen.”
One concern about the SeaCURE project is the potential environmental impact of releasing low-carbon water back into the sea. While the amount of water processed by the project is relatively small, researchers are studying the effects of adding low-carbon water to the ocean and whether it could disrupt marine ecosystems. Guy Hooper, a PhD student at Exeter University, is studying how marine organisms are affected by exposure to low-carbon water. He explains that organisms like phytoplankton rely on carbon to carry out processes like photosynthesis, and animals like mussels use carbon to build their shells. Therefore, adding too much low-carbon water to the sea could potentially affect marine life.
Hooper is conducting laboratory experiments to better understand the impact of this process. “We need to consider how this will affect the environment and whether there are ways to mitigate any potential harm,” he says. “It’s important that these discussions happen early on.”
Despite the uncertainties, the SeaCURE project offers a promising glimpse into the future of carbon capture technology. While the pilot project is small, it has the potential to be scaled up and integrated into a larger strategy for tackling climate change. As global temperatures continue to rise and the effects of climate change become increasingly apparent, innovations like SeaCURE could be crucial in helping the world meet its carbon reduction targets.
Dr. Oliver Geden, an expert in carbon capture from the Intergovernmental Panel on Climate Change (IPCC), notes that capturing carbon directly from seawater is one of many options being explored. “There are around 15 to 20 different options for carbon removal,” he says. “Ultimately, the question will come down to cost and what works best in different contexts.”
As the world moves closer to its climate goals, projects like SeaCURE could play a key role in shaping the future of carbon capture and helping mitigate the impact of climate change.
