4 billion tons yearly: UK starts sucking carbon from sea with floating solar power

Efforts have begun to suck carbon out of the sea on England’s south coast. A new project called SeaCURE has been launched to process the seawater to remove the carbon before pumping it back out to sea, where it absorbs more CO2.

Funded by the British government, the small pilot scheme is part of the administration’s effort to search for technologies that fight climate change.

The project began because there have been claims that stripping carbon dioxide out of the ocean could be much more efficient than capturing it from the air.

Carbon-absorbing capacity

With a pilot plant at Weymouth, experts are aiming to prove their claims. The project received £3 million from the UK government to test the feasibility of leveraging the ocean’s natural carbon-absorbing capacity to help address climate change.

Reports have revealed that oceans absorb about a quarter of all human-produced CO₂ emissions. SeaCURE, one of 15 UK-backed projects investigating scalable carbon removal strategies, targets the higher concentrations of carbon dissolved in seawater.

The team is currently exploring the impact of their methods on marine organisms that rely on dissolved carbon. Initial results have suggested some impacts, but the team is exploring mitigation strategies like pre-dilution.

Reports revealed that the amount of CO2 the project is removing is currently tiny, at most 100 metric tons per year, about the carbon footprint of about 100 transatlantic flights. But given the size of the world’s oceans, those behind SeaCURE think it has potential.

Project could be scaled up to remove 14 billion tonnes of CO2

In its submission to the UK government, SeaCURE said the technology could be massively scaled up to remove 14 billion tonnes of CO2 a year if 1% of the world’s seawater on the ocean’s surface was processed, reported BBC.

The system of SeaCURE, which is similar to capturing the CO₂ bubbles from a fizzy drink, makes use of renewable energy to remove carbon from seawater, then releases that seawater back to the ocean where it naturally replenishes the lost CO2 by sucking carbon from the atmosphere. 

The innovative technology pulls ocean water to an onshore processing point, raising its acidity, causing the naturally accumulated CO2 to be released in gas form. Once released, the CO2 is then sucked away and treated with charred coconut husks to increase its concentration, creating a carbon dioxide stream that is ready to be safely stored.

Reports revealed that the resulting low-carbon seawater is treated with alkali to bring its acidity back to normal levels before being released into the ocean, where it will continue absorbing atmospheric CO2 through naturally occurring processes. 

Capturing carbon gives the hard-to-decarbonize sectors a chance to develop zero-carbon technologies without contributing further to the climate problem. Reports have highlighted that carbon removal could dramatically improve the rate at which atmospheric CO2 can be stabilized and reduced toward pre-industrial levels.