The process is energy-intensive and expensive, and it has a large environmental footprint. It produces greenhouse gases as well as concentrated salts, known as brine, which are pumped back into the oceans and are detrimental to the marine environment. For every litre of water produced, the process creates about 1.5 litres of brine. These factors limit the expansion of desalination and its ability to keep up with the rising demand for potable water in Gulf countries including the UAE.

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