Undersea Desalination Pods To Solve Water And Energy Woes

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Last Updated on: 17th August 2025, 06:35 pm

The bottomless energy-sucking demands of AI data centers have sparked a hair-on-fire moment for the nation’s electricity grid, and that is not the only urgent grid-related issue in need of attention. Seawater desalination is another one of modern life’s great energy suckers, and the need is escalating alongside climate change and population growth among other factors. One solution has surfaced in the form of undersea desalination “pods” that can trim energy use by 40%, among other benefits, and the plan is poised for rapid scaleup.

Desalination And Location, Location, Location

Conventional desalination systems need large amounts of energy to power reverse osmosis systems, in which water is pressed through a membrane. Instead of sourcing that pressure from fuels of various sorts, the California startup OceanWell is leveraging the naturally occurring pressure of deep ocean water. Its pod-like desalination modules are designed for deployment in the ocean at 400 meters (about 1,300 feet).

There being no such thing as a free lunch, the energy and expense required to bring the newly desalinated water ashore could offset much of the savings from natural water pressure. The in-ocean location also poses some challenges for repairs and routine maintenance. However, OceanWell is confident that the overall effect will be an economical one.

The company also points out significant additional benefits. Putting the bulk of desalination infrastructure out at sea instead of crowding it into already-crowded coastal communities is one key difference that can save money on start-up costs — and time, especially. Water industry observers like to point out that the California city of Huntington Beach began considering an 11-acre onshore desalination facility right around the turn of the 20th century, only to see the California Coastal Commission drop the hammer on the project in 2022, after more than 20 years of discussion.

The 11-acre onshore site would have desalinated 50 million gallons of seawater per day, but it fostered concerns about climate impacts. When the CCC advised Huntington Beach to kill the project, they pointed out that the proposed site was vulnerable to sea level rise.

From One Desalination Pod To Many

Aside from avoiding direct sea level rise impacts, the in-ocean location also enables the pods to diffuse leftover brine from the desalination process more effectively, reducing the need for expensive environment-protecting equipment.

OceanWell floated across the CleanTechnica radar last year in November, when it began working on a pilot project under the umbrella of the Las Virgenes Municipal Water District. At the time, the company already had its sights on expansion. Plans were in motion for 15 “water farms” in California and elsewhere. If that sounds a little overly ambitious, perhaps so. However, along with assistance from two dozen other California water districts, OceanWell has caught the eye of the US Navy and its unquenchable thirst.

“In its search for more fuel efficient ways to provide drinking water for long sea voyages and remote bases, the U.S. Navy has developed a second-generation desalination unit that use 65% less energy than conventional technology,” CleanTechnica noted all the way back in 2009, taking note of a new, compact on-board desalinator featuring a high-efficiency pump.

The search has continued ever since. OceanWell states that the Navy made its deepwater simulation facility available for testing earlier iterations of its underwater pod system.

Green Light For Water-Producing Pods

Earlier this year, OceanWell began testing a single pod in an onshore reservoir. A real-life look at the efficiency of its intake system is one of the goals of the shakeout. The reservoir is an active, biodiverse site and OceanWell has designed its pods to minimize impacts on aquatic life on both the intake and brine disposal sides.

Apparently, they have seen enough, and so have their partners. Last week, OceanWell announced that plans are underway to scale the company’s Water Farm 1 project from 10 million gallons of water per day to 60, as six other water districts have piled on to the project.

To get to the 60 MGD mark, Water Farm 1 will consist of dozens of pods located in Santa Monica Bay, about 4.5 miles off the coast of Malibu. “WF1 offers a new model that reduces pressure on strained systems like California’s Bay-Delta system and the Colorado River and unsustainable aquifer extraction, helping secure a more resilient, climate-aligned water future,” OceanWell notes.

“California, like much of the world, urgently needs a new source of water to replace dwindling supplies,” said OceanWell CEO Robert Bergstrom in a press statement.

Las Virgenes GM Dave Pedersen also chipped in his two cents. “Las Virgenes water customers were severely impacted by recent droughts, because our only source of supply is the water imported through the State Water Project, which has become increasingly stressed,” Pedersen explained.

Bergstrom also underscored some additional advantages of at-sea desalination in California. In addition to avoiding the fallout from rising sea levels, Bergstrom noted that onshore infrastructure is vulnerable to rapidly melting snowpack and more extreme atmospheric rivers.

Next Steps For Fresh Water

Don’t get too excited just yet. Adding six more water districts to the Water Farm 1 project is a complicated effort that will require a reworking of the onshore water distribution system. A feasibility study is the next step, and the results of the study will inform investment strategies as well as the permitting process.

On the plus side, solutions are at hand. The City of Burbank, for example, joined the Water Farm 1 consortium even though it does not have the infrastructure to receive fresh water directly from the desalination pods. Instead, the city plans to work with the Metropolitan Water District of Southern California on an exchange system.

“Burbank will pay for the delivery of OceanWell water to other partners in Water Farm. The water can then be exchanged between partners within the consortium by using water within MWD’s system,” explains Burbank Water and Power Assistant GM Richard Wilson.

Assuming that onshore complications can be resolved, OceanWell has also tasked its Tribal and Environmental Working Groups to review the results of pilot stages, in order to configure the Santa Monica Bay array in accord with environmental and community concerns.

Data Centers & Desalination

Although drinking water is OceanWell’s current priority for seawater desalination, Water Farm pods could be put to other uses. If you’re thinking a green hydrogen angle is in play, drop a note in the comment thread.

Data center cooling is another potential application that would help alleviate stress on land-based freshwater supplies. Though, other solutions are also emerging. The underwater data center startup Subsea Cloud provides one such example. Geothermal energy cooling is another potential option.

Then there’s the idea of shooting data centers up into space where the natural cooling force of the universe can go to work, but that’s a whole ‘nother kettle of fish.

Image (cropped): The US startup OceanWell is scaling up its plans to deploy modular pods under the sea for energy efficient seawater desalination.