By 2016, if you live in San Diego, you’ll be drinking seawater. Every day, the county’s massive new desalination plant will turn up to 54 million gallons of ocean water into freshwater as insurance against continuing drought. But it’s not a solution that can easily spread elsewhere, despite the fact that much of the population of California–and some other drought-stricken places–lives near the coast. The plant cost $1 billion to build.
A new design from GE, unveiled at Fast Company‘s Innovation Festival, is much smaller and mobile–and much cheaper. Using 3-D printed steam turbines, a miniature version of the machines that spin in power plants, the new technology sends seawater through a hyper-cooling loop that freezes it. The salt naturally comes out, and the result is clean drinking water.
The process uses about eight times less energy conventional desalination, where water is evaporated with heat. “Freezing water is a not a new approach, but the economics have not been great because the water recovery has typically been very low,” says Vitali Lissianski, a chemical engineer in GE’s Energy Systems Lab. “We believe with the unique approach we are taking to freeze the water through our mini-turbine, all of the water could be treated.”
Using dramatically less energy also means much lower costs; the company estimates that it could be as much as 20% cheaper. And that might be enough to make it spread more widely and provide a more viable solution for drought. “97.5% of the Earth’s water supply is virtually inaccessible because water desalination is still too expensive and difficult to deploy at a large scale,” Lissianski said in a release. “By putting desalination ‘on ice,’ we hope to change that dynamic.”