MAYS IBRAHIM (ABU DHABI)

Researchers in the UAE are advancing a new generation of desalination technologies tailored to the Gulf's harsh marine environment, with the aim of cutting energy consumption, limiting environmental damage, and unlocking value from waste.

At NYU Abu Dhabi, scientists have recently patented a technique that converts used plastic bottles into filtration membranes capable of purifying water, Professor Nidal Hilal, director of the university's Water Research Center, told Aletihad in an interview.

This innovation comes as part of NYUAD's broader push to move desalination away from energy-intensive, wasteful methods toward more efficient and circular systems.

Desalination plays a central role in water security across the Middle East, which now hosts nearly half of the world's total desalination capacity. However, rapid population growth, urban expansion, and shrinking groundwater reserves have placed mounting pressure on traditional freshwater sources. 

By 2022, the region was producing roughly 45 million cubic metres of desalinated water per day, with the UAE and Saudi Arabia leading in output. A five-decade research review conducted by NYUAD researchers projects that this figure will rise to around 60 million cubic metres per day by 2027.

While global desalination has largely shifted toward membrane-based methods such as reverse osmosis (RO), thermal plants still account for around 50% of installed capacity in the Middle East. By contrast, more than 95% of global desalination outside the region uses non-thermal technologies.

According to Professor Hilal, reverse osmosis consumes roughly one-tenth of the energy required for thermal desalination, yet adoption in the region has been challenged by its seawater conditions.

The Arabian Gulf has some of the highest salinity levels in the world – around 45,000 milligrams per litre of total dissolved solids compared with roughly 32,000 in most oceans.

The water is also highly turbid, causing membranes to foul more quickly and increasing energy use.

"That means we can't simply import solutions designed elsewhere," Professor Hilal said.

To address this, the Water Research Centre engineered polymer-based membranes embedded with nanomaterials that reduce fouling: the accumulation of unwanted material on membrane surfaces that drives up energy use and operating costs.

Their work resulted in the first RO membrane module developed entirely in the UAE, unveiled in 2024. By boosting repulsive forces at the nanoscale and reducing adhesion, the membranes can operate longer and more efficiently.

This is complemented by a surface-patterned membrane that integrates the function of traditional plastic spacers directly into the membrane itself, improving water flow while reducing fouling.

Together, these innovations have delivered energy savings of between 20% and 25%, according to Professor Hilal.

Beyond efficiency gains, NYUAD researchers are addressing desalination's largest by-product: brine. The highly saline waste stream is typically discharged back into the sea, where it poses risks to marine ecosystems.

Professor Hilal said this waste stream contains valuable minerals - including sodium, magnesium, lithium, and even silver - that are largely lost.

"What used to be waste, we now believe are resources," he said.

The centre has developed membrane technologies capable of selectively extracting minerals from brine, including fully stripping silver in laboratory settings.

With global demand for battery materials such as lithium accelerating, desalination plants could one day serve as both water producers and sources of strategic minerals, he noted.

These solutions are particularly relevant for the UAE, which has long relied on thermal desalination to meet demand amidst limited natural water resources.

Today, desalinated water constitutes around 42% of the country's total water supply, produced by approximately 70 major desalination plants that together produce roughly 14% of the world's desalinated water. In Abu Dhabi, desalinated water makes up about 30% of total water resources, according to the Department of Energy.

The emirate alone is responsible for roughly 9% of worldwide desalinated water output, with an installed capacity of around 960 million imperial gallons per day (about 4.13 million cubic metres) across nine desalination plants.

A key contributor is the Al Taweelah RO, the world's largest reverse osmosis desalination facility with a capacity of about 909,000 cubic metres per day.

Looking ahead, DoE forecasts for water production in Abu Dhabi indicate that reverse osmosis will account for nearly 90% of Abu Dhabi's water production by 2030, up from 27% in 2022.