Since the early 1800s, the ocean has become ~30% more acidic. The result: an endangered marine ecosystem that’s killing coral, dissolving sharks’ teeth, and threatening our food supply.
Luckily, Planetary, a Canadian geoengineering startup founded in 2019, is tackling the issue with a novel approach to carbon capture: feeding the ocean antacids.
How it works
Planetary’s method simply speeds up a natural process through something called ocean alkalinity enhancement (OAE):
- The company adds alkaline minerals — specifically, magnesium hydroxide — to seawater to neutralize carbon dioxide, transforming it into bicarbonate ions that can store carbon for 100k years.
- It partners with coastal power plants and wastewater facilities that already funnel water into the ocean to deposit its antacids through their pipes.
- Instead of producing or buying the antacids, Planetary sources and purifies alkaline waste products from industrial sites that would otherwise end up in landfills.
Plus, relying on existing infrastructure keeps costs low. Carbon removal companies target costs of $100 or less per ton; Planetary claims it could whittle that price down to $17, per Fast Company.
However…
… the research on the efficacy and potential consequences of OAE is currently limited, and some experts are skeptical.
Melissa Meléndez, an oceanographer at the University of Hawaii at Mānoa, told FC that “some minerals could introduce trace metals that might be harmful to marine ecosystems.”
But others argue the risks posed by climate change and ocean acidification are larger, and that carbon capture, alongside cutting emissions, is necessary to curb the effects of climate change.
- The National Oceanic and Atmospheric Administration found OAE to be the most effective long-term solution for capturing carbon and one of the cheapest.
But to do that, it’ll have to scale
So far, the company has sold carbon removal credits to Shopify, Stripe, and British Airways, and recently cut a $31m deal with Frontier — a carbon removal buyer coalition working with companies like Google and H&M — for 115k+ tons of carbon removal over the next four years.
But the goal is to scale into the gigatons.
- Scientists estimate that ~7B-9B metric tons of CO2 will need to be removed annually by 2050 to limit global warming to 1.5-2 degrees Celsius.
Thanks to the low costs and minimal energy requirements of Planetary’s tech, that potential seems well within the tide of possibility.
