“The world isn’t short of water, it’s just in the wrong place, and too salty”.
The above quote isn’t from a hugely famous individual. Or at least its source, Charlie Paton, isn’t yet. However, the sentence’s simple statement of fact resonates. We are moving into a time when the latest technology in the world may well realistically mean a permanent human colony on Mars within the lifetime of many of us. Within 2 decades it’s almost certain driverless cars will be the norm and AI will have reached a level that means many of the jobs humans currently do will be automated. Yet despite all of this booster-powered technology progress taking place in the world’s wealthy nations, huge swathes of regions humans live in are barely habitable due to drought and famine.
Returning to Paton’s statement, we don’t have a shortage of water. What we have is a shortage of freshwater and an even more pronounced shortage of readily accessible freshwater. As little as 1% of all of the world’s freshwater is defined as ‘readily accessible’ and 50% of reserves are found in 6 countries -China, Brazil, Canada, Russia, Indonesia and Columbia. Over 30% of the world’s nations are considered to be ‘water stressed’, meaning that their consumption needs are at least 20% higher than the supply available to them.
So what’s the solution? 70% of the world’s freshwater is locked up in ice caps. We don’t want that to change, though it is. Ice caps melt into the sea and the freshwater becomes salt water. And the rising sea levels and climate change that results in is a huge problem in itself. So scratch that option. Another interesting stat is that 92% of the water on Earth is salt water. We have, relatively speaking, plenty of salt water. With all of the technology advances of recent decades, a process that is accelerating at a remarkable pace, there must be a burning question around why we can’t yet efficiently convert salt water into freshwater and transport it to where it’s needed.
That’s exactly what Charlie Paton’s company, Seawater Greenhouse, does. His company has created a farming oasis in the desert in Somaliland, an autonomous but internationally unrecognised territory of Somalia. This is achieved by using solar power to pump water from the nearby ocean, desalinate it on site and irrigate the crops which are grown in huge greenhouses.
The technology is actually pretty basic. What’s more interesting is the science behind it. Sunlight is great for plants. The problem is, in particularly hot, arid regions the benefits of copious amounts of sunshine is negated by the increased water intensity of agriculture. That’s where the greenhouses come in. Double-layered fibreglass roofs let sunlight through but capture and divert heat through ducts. It is then used to desalinate salt water pumped from the sea using solar power. That is then used to both irrigate the crops and vapourised into cooling spray.
The system was first used in desert regions in the Middle East and Australia. When the Somaliland project came up, Paton’s first instinct was it would be too expensive to be practical. Paton went back to the drawing board and stripped the system back. The result is what Paton calls a “grown-up Bedouin tent”. The one-hectare greenhouse is made of photoselective netting that deflects hot infrared light and the desert’s winds are used to circulate water vapour internally, cutting out the need for fans and cutting costs in half.
There are higher-tech versions of Paton’s invention in more developed parts of the world but they are unaffordable in most of the world’s regions that need them the most. Paton believes that diverting humanitarian aid from food to technology like his is what will make a difference to regions most affected by drought and famine. Food aid made little dent in the problem and even sometimes denies local farmers a living when they do have a harvest. However, tech that facilitates self-sufficiency will allow these regions to finally move forward economically, which is also key to improving the political instability that has led to so many wars. Sending manned missions to Mars is great but maybe some of our tech advancements being applied closed to home would be even better.