The ocean produces roughly half of Earth’s oxygen supply and is the planet’s greatest carbon sink, a place where the environment naturally sequesters carbon. However, recent studies have found that the ocean’s ability to sequester human-caused carbon may be waning. Is there a way to reverse this trend? Marine carbon sequestration startup Gigablue thinks the answer is yes, and the company believes its technology can make it happen. 

Gigablue brands itself as the largest supplier of affordable, gigaton-scale marine carbon dioxide removal. A gigaton is equivalent to one billion metric tons—for perspective, one metric ton of carbon is comparable to the carbon emissions from a 3,000-mile round-trip flight or driving a car for 2,500 miles. The company aims to sequester one gigaton of carbon per year. 

To achieve this, Gigablue utilizes artificial intelligence to analyze the ocean and identify the world’s optimal locations for marine sequestration. Once a site is selected, the company uses biomimicry, a process that involves developing systems and materials to mimic natural biological processes, to enhance natural carbon sequestration. Gigablue has engineered natural, nontoxic particles that, when released in specific areas, will safely harness the power of phytoplankton carbon fixation. 

Phytoplankton are tiny photosynthetic organisms that play a significant role in carbon sequestration, accounting for approximately 40 percent of global carbon fixation. Carbon fixation is a process in which inorganic compounds, such as carbon, are absorbed by living organisms and converted into biomass. However, only about 1 percent of phytoplankton that absorb carbon reach the bottom of the ocean floor, where it can effectively be sequestered, stored, and removed from the food chain. 

Gigablue’s particle technology is designed to stimulate phytoplankton growth and increase the amount of carbon that reaches the ocean floor. The particles they release into the ocean float for several days along the ocean’s surface, encouraging the growth of phytoplankton. They then sink rapidly to the ocean floor, taking phytoplankton (and the sequestered carbon) with them. 

The company asserts that this form of carbon capture is cost-effective. “Every time we go to the ocean, we generate hundreds of thousands of carbon credits, and this is what we’re going to do continuously over the upcoming years and towards the future, in greater and greater quantities,” co-founder Ori Shaashua said. While the price of Gigablue’s carbon credits is not publicly disclosed, the credits are sold through offtake agreements (long-term contracts for a specific quantity of carbon), which experts estimate cost roughly 35 percent less than other forms of carbon capture. Gigablue recently achieved a huge carbon credit milestone, entering into an offtake agreement with SkiesFifty to sequester 200,000 metric tons of carbon over the next four years. 

On the surface, Gigablue’s innovation is entirely good news. However, not everyone is convinced. Scientists are concerned about the material makeup and impact of Gigablue’s particle technology. Ken Buesseler, a senior scientist at the Woods Hole Oceanographic Institution and an expert in enhancing marine carbon sequestration, is concerned that the introduction of particles could harm the ocean, stating that the notion of particles having zero effect is “almost inconceivable.” Buesseler and others have a reasonable concern, one that Gigablue can address by being transparent, continuously innovating, and making data publicly available. 

Others are skeptical about whether Gigablue’s carbon capture technology will reduce net carbon emissions or if it merely provides a way to rebrand high-emitting activities, organizations, and industries as environmentally friendly. This criticism is not limited to just Gigablue’s activities—there has long been a debate over whether the positive effects of carbon sequestration are overstated. Carbon capture technologies continue to improve, and data coming from these projects will likely influence the discussion on how big a role they should play in carbon reduction over the coming years. 

It is not wrong to be skeptical of claims that a single new technology will be the one thing to solve climate change. However, the fight against climate change needs innovation and new solutions from the private sector, including those proposed by companies like Gigablue. As the ocean struggles to capture human-caused carbon, innovation to support marine carbon sequestration is necessary. 

Time will tell if Gigablue’s impact is overstated. However, like all emerging climate solutions, the technology must be developed, tested, and refined to its full potential. In the global search for scalable and cost-effective climate solutions, efforts like Gigablue’s are worthy of applause. 

The views and opinions expressed are those of the author’s and do not necessarily reflect the official policy or position of C3.