In an effort to widen the use of a nearly limitless — but expensive — source of water for California and other places worldwide that are prone to shortages, Lawrence Berkeley National Laboratory has been selected to lead a $100 million project aimed at bringing down the cost of desalination.
The money, announced this week and awarded by the U.S. Department of Energy, will fund a research consortium of 19 universities around that the country that include Stanford, UC Berkeley, UCLA and others, along with 10 private industry partners and other Department of Energy institutions, like Oak Ridge National Lab in Tennessee.
The goal, organizers say, is to reduce the cost of removing salt from ocean water to make it a more viable drinking water source for California and other areas. Closely related, planners also hope to clean up other types of water that are being largely wasted or underused so they can provide a source for cities, farms and wildlife. Those include wastewater from sewage treatment plants, “produced water” that comes out of the ground during oil exploration, and brackish water, which is often found underground and contains about one-third of the salinity of the ocean.
“Our entire water systems in the 20th century were designed around using water once and throwing it away,” said Peter Fiske, director of Berkeley Lab’s Water-Energy Resilience Research Institute. “We need to use it more wisely by reducing, reusing and recycling it.”
A chief aim of the project, called the National Alliance for Water Innovation, is to bring the costs down of the alternative water sources so that they are competitive with traditional sources in 10 years, Fiske said.
That would reduce the need to move freshwater long distances. It also would boost supplies for cities, farms and wildlife during major droughts, like California’s recent severe drought, which stretched from 2011 to 2017. And it could help countries in arid parts of the world meet their water needs as the climate continues to warm.
Other water experts noted that such alternative sources of water are already in use but in a limited way.
“Cost is the holy grail,” said Ellen Hanak, an economist and director of the Water Policy Center at the Public Policy Institute of California in San Francisco.
“If they can significantly make a dent in that, it will be very helpful, not just to California, but worldwide,” she said. “A concerted effort on this is exciting. I wish them great success. But it’s not going to suddenly become 60% of our water supply. These are going to remain alternative, useful supplies that are especially relevant in certain places depending on what else is available.”
Alternative sources like desalination, water recycling and stormwater capture make up 2% to 3% of California’s supply now, according to a recent Public Policy Institute study. But they are growing.
Of all the possibilities, ocean desalination is the one that often attracts the most public interest.
Four years ago, the San Diego County Water Authority opened the largest desalination plant in the United States. Located in Carlsbad, the $1 billion project provides 50 million gallons a day of drinking water, or roughly 7% of the San Diego region’s water supply.
The city of Santa Barbara recently modernized and expanded a smaller desalination plant built in the early 1990s that was shuttered due to high costs when rainy years returned. And other areas, including the Monterey Peninsula, are considering building seawater desalination projects.
But because of the enormous amount of energy required to force massive amounts of salty water through extremely fine filters 24 hours a day, seven days a week — at higher pressure than water in a fire hose — so it is pure enough to drink, the cost of desalinated water can be five times more than water from other sources.
Water from the San Diego desalination plant costs roughly $2,100 an acre-foot to produce, for example. By comparison, water that the Santa Clara Valley Water District purchases from the Delta, via the state and federal government, costs about $400 to $500 an acre-foot.
An acre-foot is 325,851 gallons. It is about the amount that a family of five in California uses over a year.
Lawrence Berkeley Lab, located in the Berkeley hills above the UC Berkeley campus, was founded in 1931. Its scientists have won 13 Nobel prizes and helped design the atomic bomb during World War II.
In addition to the $100 million in federal money, other partners in the project plan to put up $34 million.
Fiske said that among the new technologies the partnership will study are more efficient ways to remove salt from water.
“Reverse osmosis squeezes saltwater through membranes,” he said. “You can also use electric fields, like an electromagnet, to pull salt ions to the side and have the fresh water flow through.”
In any desalination plant, what to do with the brine that is left over is a major issue. For many coastal plants around the world, the water is mixed with other types of water, usually from a sewage treatment plant or power plant, and diluted before it is pumped back into the ocean. But that brine may have a value, Fiske said, if scientists can transform it into bleach, hydrochloric acid or other materials that industry would pay to acquire.
Artificial intelligence systems could help run desalination plants more cheaply, he noted.
Hanak said that in her view, brackish desalination, particularly in inland areas, seems to have among the highest potential. It’s cheaper to create usable water from it than ocean water — usually about half the cost — and if the costs come down enough, it could offer inland areas far from the coast, like California’s Central Valley, a potential new water source for agriculture, she said.
Some agencies, like the Alameda County Water District in Fremont, already filter brackish groundwater to help boost supplies.
“I do not imagine us having 50 ocean desalination plants up and down the coast of California,” Hanak said. “There are a lot of cheaper sources still for urban supply.”
