Is Desalinisation the Solution to the Global Water Crisis?

By the year 2025, around 1.8 billion people will live in areas of extreme water scarcity. A new report however has suggested that desalinisation, the process whereby salt is removed from sea-water to create drinking water, may be an effective solution to the problem. Already, global desalinisation rates are dramatically increasing.

By 2016, the process will be producing 10 billion gallons of freshwater, double the amount of 2008. However, too many obstacles still lie in the way of large-scale desalinisation and the process remains unviable for poorer countries. The process of desalinisation occurs through the use of reverse-osmosis membranes that allow water to pass through but prevent larger particles such as salt and ions from doing so.

The technology has dramatically improved since their invention in the 1960s but they are still prone to ‘bacterial fouling’ that sees water-bourne bacteria clogging up the membranes and preventing water from passing through. Chlorine as a solution is not currently viable as the strong chemical degrades the thin membranes. Also, there is the problem of disposing of the salty brine, the by-product of the process, particularly in in-land communities.

But the largest hurdle for the mass use of desalinisation plants (like the UK’s Thames Gateway facility, pictured) are their cost. Reverse-osmosis membranes are currently quite expensive and new research and development is needed to standardise the technology to drive down prices, according to Yoram Cohen, a chemical and biomolecular engineering professor at the University of California, Los Angeles.