Roughly 40 percent of the world’s population—2.3 billion people—lives in water-stressed areas. According to the World Health Organization, another billion don’t have access to clean, piped water. To address the issues of water scarcity and food security, many areas of the world are now using solar powered desalination plants to produce fresh water and encourage agricultural self-sufficiency.
In dry places, the benefits of boundless sunshine are overwhelmed by the extreme heat and dryness, meaning farming becomes water intensive. Containing over 97.2 percent of the planet’s water resources, the ocean offers the potential for an abundant and steady source of fresh water purified from the vast oceans. As of 2015, roughly 18,000 desalination plants were in operation worldwide, 44 percent of them being located in the Middle East and North Africa. All told, they produce 22,870 million gallons of drinking water a day. The soon-to-be-completed Al Khafji desalination plant in Saudi Arabia will produce 60,000 cubic meters of water per day while drawing power from a grid-connected solar-power plant—not only does this system reduce the plant’s carbon footprint by up to 40 percent, it drastically reduces fuel costs.
Sundrop Farms in Australia now produces 15 per cent of the Australian tomato market – all of it grown using desalinated seawater. In Somalia, Seawater Greenhouse Company’s desalination plant produced its first harvest of lettuce, cucumbers and tomatoes in January—less than a year after its launch. Founder Charlie Paton is driven by the challenge of enabling agricultural self-sufficiency in places where it was once deemed impossible. And he wants to leave the task of scaling up in the hands of local pastoral farmers, who make up between 55 and 60 per cent of Somalia’s population. This year he plans to build an on-site training center to teach local farmers how to grow greenhouse vegetables.
Of course, cost and power consumption aren’t the only hurdles desalination must overcome. Marine life can be suffocated from high-salinity leftovers from the desalination process. One potential solution to the intake issue is to draw the water from underground.
Despite the challenges, desalination plants are part of the many solutions to a rapidly warming planet. “Have you heard of the Shirky Principle? It’s that institutions exist to preserve the problem to which they have a solution,” Paton says. “Sending food to starving countries is this knee-jerk reaction. How much have we sent to Somalia and Ethiopia, and what dent has it really made? If some of that humanitarian aid could instead be directed towards encouraging self-sufficiency, everyone would win.”
In terms of corporate media coverage, the New York Times has published several stories about desalination plants. However, those stories, published in 2015, do not reflect the significant environmental impacts of a newer generation of technology, or their current applications in communities around the world.
Andrew Tarantola, “Seawater Desalination Will Quench the Thirst of a Parched Planet,” Engadget, October 27, 2017, www.engadget.com/2017/10/27/seawater-desalination-quench-parched-planet.
Emma Bryce, “The Decades-long Quest to End Drought (and Feed Millions) by Taking the Salt out of Seawater,” Wired Magazine, March 20, 2018, http://www.wired.co.uk/article/charlie-paton-seawater-greenhouse-desalination-abu-dhabi-oman-australia-somaliland.
Student Researcher: Katja Jeschke (San Francisco State University)
Faculty Evaluator: Kenn Burrows (San Francisco State University)