As global populations grow and water scarcity becomes an increasingly pressing issue, the number of desalination plants is growing. There are now more than 20,000 worldwide, and more than 300 million people around the world rely on desalination for some or all of their daily water needs, according to the International Desalination Association.
However, the dominant technology for seawater desalination – reverse osmosis – is now over 50 years old and has its drawbacks. Scientific innovation in this field is urgently needed to bring down the costs and energy intensity of treating water.
Scientists at Berkeley Lab have been exploring different approaches for efficiently separating out salt and other contaminants to generate water that’s fit for drinking or other uses, such as agricultural irrigation. For example, they’re looking at charge-based brackish water desalination, nanoconfinement of water, better membranes, and other advanced water treatment techniques.
Another desalination technology that has shown great promise is forward osmosis – it requires far less energy then reverse osmosis, but there are still barriers to wider adoption. Jeff Urban, one of the Foundry’s staff scientists who specializes in new materials for energy storage and conversion, explains what forward osmosis is and how Berkeley Lab is addressing the challenges.