Where CO2 Meets H2O

CALIFORNIA, January 25, 2024 – The municipal water district of Palmdale in southern California (USA) is poised to launch a pilot program to demonstrate a bold new approach to mitigate climate change. Dubbed Project Monarch, after California’s most famous butterfly, it will be housed in the district’s Pure Water Antelope Valley Demonstration Facility and will make greener clean water than ever before.

Supported by the California Energy Commission and led by the Palmdale Water District the project brings together a coalition of actors including technology provider Capture6, engineering giant Stantec, the Lawrence Berkeley National Lab, and PSE Healthy Energy.

Once operational, this project will combine two technologies: direct air capture of carbon dioxide and recycled water treatment. The facility will use the salt water byproduct of treatment as a feedstock for creating a chemical that bonds with carbon dioxide in the air and fixes it into a nonreactive mineral form known as carbonates. The process also produces drinking water, and the project once scaled will provide significant fresh water for an underserved community without any natural freshwater sources.

Everybody understands the need for fresh water—especially in dry parched California. Global demand for freshwater for home use and agriculture has increased 600 percent over the past century, and in the next few decades demand is expected to double again. That will likely double the number of water treatment plants in operation worldwide.

“What people often don’t understand is the environmental footprint of those operations. We don’t normally think of tap water as a driver of global warming, which it is. Water treatment plants around the world emit 800 million metric tons of carbon dioxide every year. That’s more than all the emissions from our global shipping supply chains (~650 million metric tons every year) and more than every single airplane flight each year combined (~750 million metric tons),” said Luke Shors, Co-founder and President of Capture6. “And the problem is only going to get worse as the world’s population continues to modernize and climate change makes rainfall patterns less predictable.”

Much of this water demand growth will be concentrated in coastal areas, and desalinating seawater is one potential solution, but it’s imperfect. Desalination is energy intensive. It burns fossil fuels, produces lots of greenhouse gasses, and makes tons of concentrated salty slurry by-product besides—so much that you could cover the entire state of Florida with a standing foot of brackish brine each year, according to a 2019 study.

Normally this brine is pumped into the ocean, which is environmentally unsound and harmful to marine life—or transported to massive solar evaporation ponds and with subsequent disposal of the resultant salts in landfill. These strategies to brine management both just perpetuate problems by moving excess salt from one place to another, and they fail to address global warming. If the solution to freshwater needs come at the zero-sum expense of reversing climate change, we won’t be balancing our priorities to find a single winner but simply creating two losers.

Facilities like the one Capture6 is piloting with the Palmdale water district through Project Monarch represent a scalable solution built on the idea that you can address two problems at the same time to the benefit of both. Once it’s up and running in early 2025, Capture6 expects the project will demonstrate how it’s possible to make fresh water, remove carbon dioxide from the air, and create new jobs all while eliminating salt waste.

The Project Monarch technology is scalable, and Capture6 estimates if similar technologies are implemented worldwide at water treatment plants, that alone would remove a billion tons of carbon dioxide annually from the atmosphere with further opportunities to reduce new emissions from the water treatment facilities themselves.

Palmdale, California’s approach is powerful as it gets us to our most ambitious climate goals in a customizable, scalable, and economically viable way. It stops the discharge of brine contaminants in ecologically harmful and expensive ways and produces water in the process. Our future is built on such synergies, and it may run straight through your nearby locality.