As more parts of the world face intense drought, new technologies are emerging to clean and reuse existing water. Investors are seeing potential for big profits.
Water treatment is expensive. It uses a lot of energy and produces its own waste that gets disposed of at a hefty price. Capture6, a startup in Berkeley, California, says it’s developing a solution, and one with an added benefit to the environment.
Capture6’s technology repurposes industrial and water treatment waste, generating clean water and capturing carbon dioxide from the atmosphere.
“That combination of water treatment, brine management, and carbon capture all at once is part of what makes us unique, what makes our process innovative,” said Capture6 CEO Ethan Cohen-Cole, who co-founded the company in 2021. “We are able to do so at reduced energy costs.”
The process is complex. It starts with the waste from any sort of water treatment process. Once the solids are removed, that waste is called brine, which is leftover water plus concentrated salt – sodium chloride. Treatment facilities usually have to pay to get rid of it.
But Capture6 takes that brine, strips out the fresh water and separates the salt into sodium and chlorine. It then turns the sodium into lye.
“That lye has the really neat property that if you expose it to the air, it will bond with CO2 and strip it from the air, and that’s the punch line to the process,” said Cohen-Cole. “We have processed the waste salt, we’ve returned fresh water to our partner, and we’ve captured CO2 from the air.”
It’s a particularly attractive proposition in areas most in need of clean water. Capture6 is working in Western Australia, South Korea, and in drought-stricken California, at the Palmdale Water District north of Los Angeles. The district is still testing the technology, but is already projecting huge cost savings in its brine management.
“It will save us 10% on that capital cost, as well as saving us 20 to 40% in operational costs,” said Scott Rogers, assistant general manager at Palmdale Water District. “We’re recovering anywhere from 94% to 98% water out of water that would just normally be wasted.”
Rogers says it’s early but when more facilities start using the technology, it will create a circular economy that can benefit the environment.
Capture6 has raised $27.5 million from Tetrad Corporation, Hyundai Motors, Energy Capital Ventures, Elemental Impact and Triple Impact Capital.
Cohen-Cole says the company’s entire process could run on renewable energy, so all of the CO2 that it captures will be net negative, improving the environment. That allows the company to generate added revenue by selling carbon credits.
It’s just one technology in a growing field of carbon capture, removal and sequestration. Others include direct air capture, burying carbon underground or injecting it into the ocean.
The Trump Administration recently canceled $3.7 billion worth of awards for new technology, including carbon capture, to fight climate change. Capture6 has received funding from the U.S. Department of Energy and from state-level sources including California, according to the company. So far, none of that has been canceled.
— CNBC producer Lisa Rizzolo contributed to this piece.
