The Untapped Potential of Desalination

Purifying seawater to create fresh water for human consumption is a mature and cost-effective technology. Further scaling and technological advances may well make it viable for agriculture and beyond.

Desalination plant in Spain in 2010. Photo by Andrés Nieto Porras. Source.

Desalination is the removal of salts and other minerals from a substance, usually seawater or brackish water—water from where fresh rivers meet salty seas. Desalination is best known for purifying saline i.e. salty water from the world’s oceans into fresh water for household use. Modern desalination capacity, as of 2022, is estimated to be about 40 billion cubic meters of water every year.¹ This is under 1% of the roughly 4 trillion cubic meters of fresh water consumed every year.² But where it is used, desalination has scaled up to become a key and even crucial source of drinking water. More than half of the world’s desalination capacity is in the Middle East, where arid but coastal countries like Israel, Saudi Arabia, and Kuwait derive half or more of their drinking water from desalination.³ Initially developed at scale in the 1960s, desalination is a relatively mature technology that has successfully prevented a scarcity of fresh household water in countries lacking access to freshwater sources, in the Middle East but also in island nations like Singapore, the Bahamas, and Cyprus.