• Home
• /
• Opinion

Greener desalination

Masdar, Abu Dhabi’s renewable energy company, is turning its attention to finding cost-effective ways to remove the salt from seawater, using renewable energy technologies such as solar power.

There is a huge need for desalination in the Gulf, the world’s driest region and home to a rapidly growing population.

In the largely desert territories of the Gulf and other parts of the Middle East, drinking water is mostly supplied from industrial processes including chemical treatments, thermal distillation and filtration by reverse osmosis. These are all highly energy-intensive – and they burn up large quantities of oil or gas, the lifeblood of the region’s economy.

Because of the steep up-front investments that they have so far required and the high cost per unit of power generated, renewable energy technologies have not been a popular alternative option for producing potable water, in the Gulf or anywhere else.

But advances in the technology and a steady decline in manufacturing costs for solar generating plants may be about to change that picture.

“While conventional seawater desalination methods account for 75 per cent of the Gulf’s demand for water, the process is energy intensive and costly,” Sultan Al Jaber, the chief executive of Masdar, said during an interview. “Coupling renewable energy with the latest in desalination technologies is the logical next step, and it also provides an avenue to spur economic growth and address the region’s long-term water security.”

With financial backing from Abu Dhabi’s investment arm Mubadala, Masdar says it plans to build three pilot plants in the next three to four years, sited in different areas of Abu Dhabi, to test innovative technologies and figure out if they have potential for large scale use.

Part of the programme will focus on a variant of semi-permeable membrane filtration technology known as forward osmosis, according to Masdar.

Other innovative technologies to be tested will include electrodialysis deionisation, membrane distillation and low-temperature distillation, while the programme also aims to explore the potential for cost reductions and improvements in the energy intensity and efficiency of established technologies such as reverse osmosis.

The programme aims to bridge the gap between promising technologies that are being developed in universities and research centres, and large-scale industrial applications powered by renewable energy.

The long-term goal of the initiative is to have a facility operating at commercial scale by 2020.

Middle Eastern and North African countries are home to 6.3 per cent of the world’s population, but the region contains only 1.4 per cent of the world’s fresh water. The Gulf region in particular has the highest water scarcity levels in the world, according to data compiled by the World Bank.

With limited surface water and depleting ground water resources, desalination is the key to meeting the inexorable rise in demand for water resulting from economic growth and expanding populations. Already, more than half of all the world’s desalination capacity is located in the Arab countries.

Yet, in the United Arab Emirates, to take just one example, seawater desalination requires about 10 times more energy than pumping water from wells. Costs are projected to increase by 300 per cent between 2010 and 2016, according to Masdar’s estimates.

The energy needed for desalination is usually generated by fossil fuels. The production of drinking water – often to be supplied at subsidised rates – uses 7 per cent of global energy, according to the US Department of Energy. So, in effect, large amounts of oil and gas are being used to generate cheap water supplies instead of earning export revenue.

“The Middle East is still in the process of addressing its long-term sustainable water access and security,” Corrado Sommariva, president of the International Desalination Association, said at the International Water Summit in Abu Dhabi.

A handful of other projects in the region also have started to explore the use of renewable energy sources to produce drinking water, but they are costly, few in number and mostly still at the early testing stage.

Last June, Eole Water, a French start-up founded in 2008, began field trials in Abu Dhabi of wind turbines designed to produce drinking water from the condensation of atmospheric humidity. The company says a turbine it has developed should be able to pull 1,000 liters of drinking water daily from thin air.

The Abu Dhabi trial is intended to test the ability of the technology to stand up to the sandstorms and extreme heat of the harsh desert environment.

Other small-scale renewable desalination initiatives in Saudi Arabia and Oman focus either on developing new desalination technologies, or on coupling renewable energy sources with conventional desalination plants. The Masdar project, in contrast, addresses both innovations in water desalination technologies and in renewable energy sources.

© IHT