Frontier buys $31M worth of antacids for the ocean

Frontier buys $31M worth of antacids for the ocean

Frontier, the carbon removal clearinghouse founded by Google, Strip, Shopify, and others, announced today that it is buying 115,208 metric tons of carbon removal credits from geoengineering startup Planetary in a deal worth $31.2 million. 

Where most Frontier deals to date have bought carbon from startups specializing in direct air capture, enhanced weathering, or bioenergy with carbon capture, the organization’s agreement with Planetary is its first to do so by enhancing ocean alkalinity.

The deal effectively prices each metric ton of carbon at $270, though Planetary says it has a plan to eventually remove carbon for less than $100 per metric ton. At full tilt, ocean alkalinity enhancement could remove over 1 billion metric tons of carbon dioxide annually.

For decades, the oceans have been dampening the effects of climate change by absorbing carbon dioxide from the atmosphere. That has slowed the pace of global warming, but it also endangers a host of marine organisms, including coral and shellfish, which depend on alkaline waters to help build and maintain their calcareous shells and skeletons.

The world’s oceans are naturally a little bit alkaline. Historically, they had a pH of 8.2, but since the industrial revolution began, it has fallen to 8.1. That might not sound like much, but pH’s logarithmic scale means the oceans are now 30% more acidic than in the early 1800s. When carbon dioxide reacts with water, it forms carbonic acid.

Planetary currently uses magnesium hydroxide to boost alkalinity, the same substance used in over-the-counter antacids. The company adds it at wastewater treatment facilities and power plants, sites that are already discharging water into the ocean. That helps minimize disruption to the coasts, and it helps Planetary keep costs down.

The startup currently has two projects, one in Nova Scotia and the other in Virginia.

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Tim De Chant is a senior climate reporter at TechCrunch. He has written for a wide range of publications, including Wired magazine, the Chicago Tribune, Ars Technica, The Wire China, and NOVA Next, where he was founding editor.

De Chant is also a lecturer in MIT’s Graduate Program in Science Writing, and he was awarded a Knight Science Journalism Fellowship at MIT in 2018, during which time he studied climate technologies and explored new business models for journalism. He received his PhD in environmental science, policy, and management from the University of California, Berkeley, and his BA degree in environmental studies, English, and biology from St. Olaf College.

You can contact or verify outreach from Tim by emailing tim.dechant@techcrunch.com.

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