Water scarcity is a global challenge with rapid population growth around the world placing extreme pressure on finite water resources.
The United Nations (UN) forecasts the world’s population to increase from 7 billion today to 9.7 billion by 2050 leading to a 55% increase in the demand for water. As a result more than 40% of people will be living in areas of severe water stress – defined as when demand for water regularly exceeds supply.
To feed a growing population, food supply must rise by 60% across the globe, meaning agriculture, which already uses 70% of all water taken from rivers and groundwater for livestock to drink and irrigate crops, will need an even bigger share of the world’s water supply.
The strain on a diminishing water supply will be felt most acutely in cities as rapid urbanisation continues unabated. Cape Town in South Africa is already experiencing severe water usage restrictions after narrowly avoiding running completely out of water earlier this year following a prolonged period of drought.
Cyril Ramaphosa, speaking before he became South Africa’s president, said the city faced “real, total disaster”. It was the world’s first metropolis to face such a fate.
The UN expects 66% of the global population to be living in cities by 2050 and this increase from the current 55% could cause major disruption if suitable water technologies are not in place to serve demand.
Here in the United Arab Emirates (UAE) - one of the most arid parts of the world with little rainfall - groundwater levels are low and in steady decline. For the UAE and about 150 other counties on the coastline with minimal rainfall and little freshwater, there is currently little choice but to rely on desalination technology.
Desalination is already widely used, with more than 300 million people relying on desalinated water for some or all their daily needs, according to the International Desalination Association.
Desalination has been vital for the UAE’s rapid growth and development with the country getting 96% of its domestic water through this method.
Two of the big disadvantages of desalination technology are closely linked to each other – firstly, desalination is energy intensive, and secondly these energy needs have historically been met by fossil fuels. In the UAE, seawater desalination needs about 10 times more energy than surface, freshwater production.
In the Gulf region alone, desalination plants account for 0.2% of the entire world’s electricity consumption. However, these challenges are now being addressed and desalination technology is expected to play a key role in serving growing demand for fresh water.
Energy accounts for around 70% of the cost of desalination. By reducing energy intensity and running desalination plants on renewable energy, operators could both reduce their operating costs and minimise their carbon footprint.
In the UAE, Abu Dhabi Future Energy Company (Masdar) - has piloted five energy-efficient seawater desalination projects at a testing facility at Ghantoot. The long-term goal is to implement renewable energy-powered desalination plants in the country, as well as the wider region, and to have a commercial scale facility operating by 2020. Once rolled out, this project is likely to have implications well beyond the Middle East.
Desalination technology has played a key role in helping the UAE and other countries in water scarce regions grow their cities and industries. Over the next decades, it will also be vital in helping emerging economies develop, although how these countries power their plants will be different.
Desalination, when combined with renewable energy and potentially energy storage, will significantly improve the economic viability of processing sea water and make it more environmentally sustainable. This will play a critical role in responding to the growing global challenge of water scarcity.
Of course, diversifying supplies of water and reducing energy demand from water production, is only part of the solution to water scarcity. Making better use of water – such as re-using wastewater for irrigating crops (after it has been filtered), or for industry (for heating and cooling), is another challenge.
Re-using wastewater is now common. Recent advances in technology and purification methods mean that it could have a bigger role in alleviating water scarcity.
Finding solutions to water scarcity will require governments to work closely with business. Companies are increasingly concerned about the shortage of water because it could increase the cost of producing their products and services and increase their energy costs. Over the coming decades, access to a reliable and clean supply of water could become as important to companies as access to skilled labour, capital and technology.
Cape Town narrowly avoided Day Zero this year when the taps to the city finally ran dry. Lasting solutions need to be developed and implemented before scores of other cities around the world face a similar crisis.