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Scientists want $60 million to try to capture carbon dioxide from the seabed off the coast of Canada.
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They say reactive basalt rock across the planet could turn CO2 into rock at the bottom of the ocean.
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Offshore factories to capture carbon emissions could help fight climate change in the future – at a high price.
A major solution to the climate crisis may lie at the bottom of the ocean.
Across the planet, basalt rock deposits on the seafloor have the potential to trap carbon dioxide, removing the heat-trapping gas from our atmosphere.
That is why a team of scientists wants to build floating platforms at strategic offshore locations. Instead of extracting oil from the ocean floor – as offshore platforms currently do – these futuristic platforms would inject CO2 into it.
The floating stations, powered by their own wind turbines, suck carbon dioxide from the air (or even from seawater) and pump it into holes in the seabed.
The scientists call their project Solid Carbon because, if it works as they expect, the CO2 they inject will be rock on the ocean floor forever.
“That makes carbon storage very sustainable and very safe,” Martin Scherwath, a geophysicist working on the project and a staff scientist at Ocean Networks Canada, told Business Insider.
Unlike other storage technologies, we don’t have to worry about carbon returning to the atmosphere and global temperatures rising.
It’s not yet certain whether these oceanic carbon removal plants would work as expected. For one thing, scientists need about $60 million to test a prototype at sea.
How the bottom of the ocean could remove carbon from the air
The scientists estimate that basalt rocks worldwide could permanently store more carbon than all the fossil fuels on Earth can emit. Just look at this map of potential locations around the planet, highlighted in yellow.
That doesn’t mean it’s safe to continue burning fossil fuels indiscriminately. This strategy is unlikely to be technologically, politically and economically feasible in every location on the map. It will also be slow and expensive to scale.
Still, the scientists say just a few installations can make a big difference. According to Scherwath, the Cascadia Basin off Canada’s west coast, near Vancouver Island, has room for about 20 years’ worth of global carbon emissions. They hope to conduct a field test there.
“The reason that location is so attractive is that it’s probably the place on Earth where we know the most, have the most data, the most scientific expeditions, the most studies on the nature of the ocean crust,” says David Goldberg. a geophysicist and professor of climate science and carbon management at Columbia University who has been developing this idea since 1997, told BI.
The plan is based on a chemical reaction that occurs naturally. Basaltic rock is highly reactive and full of metals that easily absorb CO2 and chemically bond with it to form carbonate minerals.
The basalt also tends to be fractured and porous, leaving plenty of room for new carbonates to fill in.
In Iceland, a project called CarbFix has proven a small-scale version of this process, which involves dissolving CO2 in water (yes, that’s sparkling water) and injecting it into underground basalt.
Within two years, the CO2 gas mineralizes, ending up deep underground.
The final piece of reversing climate change
These oceanic carbon sinks would be a massive and costly undertaking – exactly the kind of megaproject we may eventually have to resort to if we want to cool the planet back to pre-industrial temperatures.
“We have to come up with the money. I don’t think there’s any way around it,” Scherwath said.
That said, Solid Carbon is not a substitute for the fundamental, immediate actions that climate experts worldwide are calling for, including swapping fossil fuels for renewable energy and reducing carbon emissions from our food systems.
Rather, Scherwath says this is one of our later carbon capture options, decades from now, to shave off the last few tenths of a degree of global warming. But to have that option, we have to start developing it now.
According to a report from the National Academies of Science, Engineering, and Medicine, the world may need to cut 10 billion tons of CO2 every year to reach net-zero emissions by 2050 and have any chance of limiting global warming to targets . enshrined in the Paris Agreement.
To achieve that goal, “you need every last drop,” Goldberg said.
This could include restoring ecosystems that naturally store carbon, such as forests and wetlands, as well as capturing CO2 directly from the atmosphere and storing gas underground in depleted oil and gas reservoirs.
The problem with these methods is that the carbon can escape, through forest fires or through abandoned oil wells.
Scientists at Solid Carbon say carbon rocks have been stuck on the seabed for thousands of years. They also argue that there is plenty of room in the ocean to scale up and that there is little risk of disgruntled neighbors opposing the project.
“This is a good complement to the other methods, but it is also the most expensive,” Scherwath said.
Looking for $60 million
The Solid Carbon demo would involve sending out a ship carrying pre-captured CO2, drilling a hole in the seabed and injecting it there. They would use an existing cable network to monitor the site and check for escaping gas.
The problem is financing. The group has applied for federal grants in the U.S. and Canada, as well as from foundations, Goldberg said. So far, they have been unable to secure the $60 million they need to implement the pilot.
Goldberg suspects this is partly because there is no clear way to make money by capturing carbon and releasing it into the seabed.
“I mean, climate change is so expensive,” Scherwath said. “The way to think about it might be similar to the sewage treatment in cities, the way it should be done.”
If they had the money, Goldberg thinks they could start the pilot in a year or two.
Read the original article on Business Insider