This is an excerpt from an article appearing in the August 20, 2016, Science News with the headline, “Quenching society’s thirst: Desalination may soon turn a corner, from rare to routine.”
When Khaled Moustafa looks at a beach, he doesn’t just see a place for sunning and surfing. The biologist at the National Conservatory of Arts and Crafts in Paris sees the future of farming.
In the April issue of Trends in Biotechnology, Moustafa proposed that desalination could supply irrigation water to colossal floating farms. Self-sufficient floating farms could bring agriculture to arid coastal regions previously inhospitable to crops. The idea, while radical, isn’t too farfetched, given recent technological advancements, Moustafa says.
Floating farms would lay anchor along coastlines and suck up seawater, he proposes. A solar panel–powered water desalination system would provide freshwater to rows of cucumbers, tomatoes or strawberries stacked like a big city high-rise inside a “blue house” (that is, a floating greenhouse).
Each floating farm would stretch 300 meters long by 100 meters wide, providing about 3 square kilometers of cultivable surface over only three-tenths of a square kilometer of ocean, Moustafa says. The farms could even be mobile, cruising around the ocean to transport crops and escape bad weather.
Such a portable and self-contained farming solution would be most appealing in dry coastal regions that get plenty of sunshine, such as the Arabian Gulf, North Africa and Australia.
“I wouldn’t say it’s a silly idea,” Voutchkov says. “But it’s an idea that can’t get a practical implementation in the short term. In the long term, I do believe it’s a visionary idea.”
Floating farms may come with a large price tag, Moustafa admits. Still, expanding agriculture should “be more of a priority than building costly football stadiums or indoor ski parks in the desert,” he argues.
Whether or not farming will ever take to the seas, new desalination technologies will transform the way society quenches its thirst. More than 300 million people rely on desalination for at least some of their daily water, and that number will only grow as needs rise and new materials and techniques improve the process.
“Desalination can sometimes get a rap for being energy intensive,” Dave says. “But the immediate benefits of having access to water that would not otherwise be there are so large that desalination is a technology that we will be seeing for a long time into the future.”