Editor’s Note: CNN Films “Blue Carbon: The Hidden Power of Nature” takes viewers from the mangroves of Vietnam to the salt marshes of France to investigate a powerful new ally in the fight to slow climate change. It will premiere on Sunday, April 21st at 9pm ET/PT.
An oceanfront startup in western Singapore is building a facility that will convert carbon dioxide from air and seawater into the same material as seashells; The process will also produce “green” hydrogen, a much-hyped clean fuel. .
The cluster of low-rise buildings taking shape in Tuas will become the “world’s largest” ocean-based carbon dioxide removal facility when completed towards the end of this year, according to University of California-based Equatic. In Los Angeles.
The idea is that the plant draws water from the ocean, hits it with an electric current, and passes air through it, producing a series of chemical reactions to trap carbon dioxide and store it as minerals; This can be returned to the sea or used. Overland.
It’s a compelling vision of a potential solution to the worsening climate crisis that is fueling unprecedented heat and devastating extreme weather. Efforts to curb global warming are largely off track, and many scientists warn that in addition to rapidly reducing fossil fuels, the world must also eliminate the carbon pollution that humans are already pumping into the atmosphere.
This facility in Singapore is one example of many new projects that see oceans, which already absorb almost 30% of humanity’s planet-warming pollution, as a means to achieve this. Other projects include sprinkling iron particles into the ocean to stimulate CO2-absorbing phytoplankton, sinking seaweed deep to lock in carbon, and spraying the particles into marine clouds to reflect some of the sun’s energy.
But decarbonization projects are criticized for being controversial, expensive, unproven at scale and a distraction from policies to cut fossil fuels. Criticism can be even louder when it comes to oceans—complex ecosystems that are already under great pressure due to global warming.
Jean-Pierre Gatusso, an oceanographer at Sorbonne University in France, said there are “huge knowledge gaps” when it comes to ocean geoengineering in general. “I’m very concerned that science is lagging behind industry,” he told CNN.
How does it work
The Equatic technology, tested in small pilot projects in Los Angeles and Singapore, requires three main components: seawater, rocks and electricity.
The system works like this: The plant pumps seawater and passes an electric current through it, splitting it into four components: two liquids, one acid and one alkaline, and two gases, hydrogen and oxygen.
The acidic water will be mixed with crushed rocks to bring the pH to the same level as seawater and then returned to the ocean.
Fans will pump air through alkaline flow, which causes carbon dioxide to form dissolved bicarbonate as well as solid calcium carbonate, which looks like fine sand, from which seashells are formed.
Solid and dissolved minerals, which Equatic says can lock carbon for at least 10,000 years, will be returned to the ocean or used on land. Seawater will also be returned to the sea, ready to absorb more carbon dioxide from the atmosphere.
Gaurav Sant, founder of Equatic and professor of sustainability at UCLA, said no processes take place in the open ocean: “This is important because it allows you to perfectly measure everything you do.” This includes the amount of carbon locked in, as well as the electricity the facility uses.
Edward Sanders, chief operating officer of Equatic, which partnered with Singapore’s National Water Agency to build the plant, said the $20 million plant will be fully operational by the end of the year and can remove 3,650 metric tons of carbon dioxide annually. This amount is equivalent to removing approximately 870 average passenger cars from traffic.
The goal is to remove 100,000 metric tons of CO2 per year by the end of 2026, and increase that figure to millions of metric tons over the next few decades, Sanders told CNN. He said the facility could be replicated almost anywhere, stacked in modules “like Lego blocks.”
Sant told CNN they need to make sure there won’t be negative impacts as the facility scales up. “There’s a big difference between doing it on a scale of one tonne, doing it on a scale of a million tonnes, or doing it on a scale of a billion tonnes. “You need to measure, you need to monitor, you need to adapt.”
Upfront costs are high, but the company says it plans to make money by selling carbon credits to polluters to offset their pollution and the hydrogen produced during the process.
Equatic signed a deal with Boeing to sell 2,100 metric tons of hydrogen, which it plans to use to produce green fuel, and to finance the elimination of 62,000 metric tons of CO2.
fragile oceans
But the risks far outweigh the benefits, according to some critics.
Lili Fuhr, deputy director of the climate and energy program at the Center for International Environmental Law, criticized the use of “speculative technology” at a time when “climate change is already killing our oceans.”
Fuhr told CNN that processing large amounts of seawater can kill marine life. “We already know that power plants kill fish larvae and other marine life. Equatic will process much more seawater per plant than a power plant,” he told CNN, “And we need thousands of such plants to make a meaningful impact on global climate.” will be needed.”
James Niffenegger, a researcher at the National Renewable Energy Laboratory who wrote a report on ocean carbon removal, said the effects need to be closely monitored. “Artificial movement of water on this scale would be huge,” he told CNN.
The process could also potentially disrupt the delicate balance of ocean chemistry, Niffenegger said. While there is plenty of research on the negative effects of ocean acidification, there is much less research on what might happen if the ocean became more alkaline.
There are indications that impacts may be low, he added, but “we won’t understand the potential of this solution until we actually start implementing these things.”
There are also energy requirements; As the world moves away from fossil fuels, the demand for clean energy increases exponentially. “Transporting seawater will require large amounts of renewable energy that would be better used to replace fossil fuels in the first place,” Fuhr said.
This is a point echoed by Gatusso, who says that “fairness needs to be taken into account when valuable electricity is used to remove carbon rather than providing it to the population that needs it.”
Equatic said it filters seawater to ensure marine life does not enter the system, and that the water discharged back into the ocean will have the same composition as normal seawater and comply with Singapore’s environmental rules.
The company also said that the production of hydrogen, which can be used to power the process, means overall energy use is lower than other carbon removal methods.
Equatic’s project epitomizes a broader debate between those who fear that a rush to geoengineering could cause untold damage to ecosystems and those who believe the climate crisis is so severe that the technology should be an option.
It’s clear which side Equatic is on.
“Inaction is not a climate strategy,” UCLA’s Sant said, adding that being able to make decisions with uncertainty is vital. “If we are serious about mitigating the tide of climate change, we need to be willing to act, and we need to act quickly at scale,” Sant said. said.
For more CNN news and newsletters, create an account at CNN.com