An article from the MIT Technology Review describes a development by researchers at Lawrence Livermore National Laboratory that could bring clean drinking water to 2 billion people who currently don't have access to this necessity.
By using carbon nanotubes, membranes were created with pores so fine that only the width of seven water molecules could pass through. This removes many impurities, including salt molecules. These filters may reduce the cost of desalinification by up to 75%, and could come to market in the next decade. The real secret is the price of carbon nanotubes, which is expected to decline by half every 18 months. In 10 years, the price of nanotubes will be merely 1/100th of what it is today. This filter could become inexpensive enough for even small villages to operate their own desalinification facilities. This, in turn, could greatly reduce poverty, increase life expectancy, and foster economic growth.
Water is a critical component of economic growth on every level, even more so than oil. Numerous wars have been fought over water in the Middle East and North Africa, and this innovation could be yet another contributor towards the reduction of warfare through economic prosperity.
Needless to say, a massive reduction in the cost of creating highly purified water also benefits the top of the economic pyramid. Industries that use large amounts of purified water and could benefit from cost reductions are semiconductors, pharmaceuticals, healthcare, food processing, etc.
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