If there was any doubt the ocean is increasingly becoming a focus of carbon capture entrepreneurs, you may set it aside.

Three months after early-stage startup Captura — fronted by an experienced executive in the nascent carbon removal sector, former Carbon Engineering CEO Steve Oldham — raised $12 million in Series A funding, a group of former Google, SolarCity and Tesla executives in April snagged $20 million in what is being called the largest ocean-based carbon removal investment to date.

Like Captura, their company, Ebb Carbon, is betting electrochemistry can help speed up the ocean’s natural ability to sequester atmospheric carbon dioxide. It hopes to set up shop near desalination plants, seaside power plants, aquaculture operations, salt producers and other coastal industrial facilities, where its system can "intercept," treat and capture salty water flowing through wastewater pipes. That water is treated using low-carbon electricity to produce hydrochloric acid and sodium hydroxide. The acid is diverted from the ocean, but the other solution is returned, where it enhances the ocean's natural ability to capture sequester carbon dioxide.

Ebb Carbon’s new funding, led by Prelude Ventures and Evok Innovations, was closed in two rounds. The money will go toward building two of its first commercial systems: The first, which will capture a relatively tiny 100 metric tons of carbon annually, should be in place by late 2023; the second, with a sequestration capacity of 1,000 metric tons annually, will be in place "shortly thereafter," according to the funding press release. 

"We are excited by the potential for Ebb to remove gigatonnes of CO2 annually," said Gabriel Kra, managing director and co-founder of Prelude Ventures, in a statement. "The team has previously demonstrated their abilities to build and scale industrial machinery, and has invented a technology that is a least-cost solution for ocean carbon dioxide removal."

A modular approach

Ebb Carbon CEO and co-founder Ben Tarbell, a mechanical engineer who was SolarCity’s vice president of products for seven years before leading climate tech research at Google X, cited many similarities between the current state of carbon removal tech and the solar sector two decades ago. "There is a clear recognition of the need, and we need to build the technologies to do this at scale in order to have any hope" of removing 10 gigatons of CO2 annually to keep temperature increases below 1.5 degrees Celsius, Tarbell told me.

The rest of Ebb Carbon’s executive team boasts equally noteworthy credentials. The chief technology officer, Matt Eisaman, is a Google X alumnus with more than a decade of research experience at Stony Brook University and Brookhaven National Laboratory; the vice president of engineering, Dave Hegeman, developed batteries for Tesla for years; and the chief engineer, Todd Pelman, has experience with electrodialysis systems and marine engineering. 

As explained earlier, the technology works by speeding up the natural process of ocean alkalinization. It captures water at existing facilities and uses elec