Solar Desalination for a Water-Stressed World

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How two ambitious solar-powered desalination experiments in Saudi Arabia and the United Arab Emirates, may provide a blueprint for reducing scarcity of the world’s most important resource.

By Russell Sticklor

Most nations within the Muslim world in the early 21st century find themselves experiencing an uncomfortable and serious shortage of a natural resource far more important than either natural gas or oil — water. Exacerbated by population growth, climate change, and economic development, water scarcity is now a serious issue across a broad arc of the world, stretching from North Africa across the Middle East and Arabian Peninsula and deep into Central and South Asia. What can be done then to ease a growing water crisis poised to affect the Muslim world for generations to come?

One potential answer lies in combining two of the Muslim’s world’s greatest untapped natural resources — solar power and seawater. This year, Saudi Arabia and the United Arab Emirates are ambitiously pursuing plans to build the world’s first large-scale solar-powered desalination plants.

If successful, these projects would be a symbolic triumph. They would serve as proof that two virtually unlimited resources can be combined to increase fresh water supply in some of the world’s most water-stressed areas, even if by only a relatively modest amount. The success of these projects in Saudi Arabia and the UAE could also provide a technological blueprint that theoretically could be replicated in any nation with a coastline and enough sunshine. Water-stressed nations in the planet’s “sun belt” — which receives frequent and powerful sunshine for much of the year — would be particularly well positioned to benefit. It is here, within this belt, where the bulk of the world’s Muslim population lives.

Map courtesy of Flickr user Kevin Gill.

Powering Desalination: Making the Transition from Fossil Fuels to Renewables

Saudi Arabia and the UAE are among the world’s largest producers of desalinated water. These countries’ reliance on desalination — still a hugely energy-intensive process despite decades of technological refinement — is borne out of necessity. Neither country has enough surface water or groundwater within its borders, to sustain its population. Other Muslim countries may find themselves in the same situation before long.

To date, Saudi Arabia and the UAE have been able to address water scarcity issues, by powering their desalination plants with fossil fuels. Why then are these two countries looking to still-unproven solar energy technology, to power the next generation of large-scale desalination facilities?

Beyond the 21st century — and likely during the 21st century — the global economy will need to transition away from its reliance on fossil fuels as these finite resources grow more scarce. This will be true even for countries currently sitting atop massive fossil fuel reserves, such as Saudi Arabia, the UAE, and other energy titans of the Muslim world. Navigating this transition will be by no means easy. For the UAE, investing in innovative new solar-powered desalination technology, aims to kill two birds with one stone: Not only will its plant in the Ras Al Khaimah emirate bolster local fresh water supply, it will also produce clean, renewable electricity for domestic consumption.

Some experts are very optimistic about the potential of solar-powered desalination technology, to eventually catch on elsewhere. Vladimir Smakhtin of the International Water Management Institute (IWMI), and co-author of a recent research study on solar-powered desalination, recently told me via e-mail, of the wide-ranging implications, should efforts to purify seawater using renewable energy, prove successful:

Saudi Arabia and the UAE have all necessary attributes to become the leaders in this industry — lack of fresh water, plenty of sun, access to the sea and sufficient funds to invest. If they manage, in the near future, to shift their water supply sector to solar-powered desalination, it could be simply a clear proof-of-concept that this approach is capable of resolving water scarcity once and for all. It will pave the way for some other nations to follow.

A fossil fuel–powered desalination plant in the United Arab Emirates’ Ras Al-Khaimah, the same emirate that will soon be home to one of the world’s largest solar-powered desalination plants

Scientific Obstacles and Opportunities

How far away are we from being able to use this type of technology? The answer remains unclear, but in Smakhtin’s eyes, the time is now. “Technologically,” he says, “it is already mature enough to produce significant quantities of water in certain regions,” including much of North Africa and the Middle East. But before solar power can become a meaningful part of a nation’s energy-generating infrastructure, there are significant obstacles that must be first overcome, such as finding more effective ways to store solar energy, a long-standing issue.

Even in light of this major hurdle, however, ongoing research and pilot projects suggest it is only a matter of time before solar power becomes a reliable and economically viable energy source. Furthermore, despite its current technological shortcomings, it is clear solar power arguably holds the greatest potential for generating clean energy in the sun-belt countries of the Muslim world. Indeed, in a 21st century world that will need to find new power sources to fill the energy gap left by increasingly scarce fossil fuels, the Muslim world’s solar power riches have the potential to emerge as a major economic competitive advantage. In the case of North Africa, for instance, “all the countries in this area have sunny days more than 80 percent of the year,” desalination plant manager José Rafael, who has worked on projects across the region, told me via e-mail.

But although our scientific knowledge of both solar power and desalination is growing sophisticated enough to effectively combine these technologies, there are other important limits on desalination’s potential to resolve water scarcity issues. Firstly, Rafael says the biggest issue facing countries “is the large initial investment,” given the funding currently needed to install solar panel arrays and construct desalination facilities and water distribution infrastructure.

Ecological issues such as brine disposal and the potential degradation of coastal ecosystems are some of the “environmental aspects of large-scale solar desalination technology interventions that still need to be sorted out,” adds Smakhtin. Aditya Sood, Smakhtin’s research study co-author and fellow member of IWMI, admits “it will be interesting to see how Saudi Arabia and the UAE handle” such environmental challenges.

Another potential issue concerns maintenance of the solar panel components. Anwar Ahsan, a desalination expert who worked for Saudi Arabia’s Saline Water Conversion Corporation for 27 years, told me via e-mail that “humidity, moisture, and air-borne dust could be the biggest hurdles to tackle,” as these conditions might threaten panels’ ability to function efficiently.

Lastly, even under ideal circumstances, desalination alone cannot produce enough fresh water to accommodate the total water needs of the Muslim world’s rapidly growing population and developing economies, especially in the agricultural sector. Meanwhile, some populations living far away from the coast, may also find themselves unable to use desalinated water, due to the huge amounts of energy it requires to transport desalinated water inland, over long distances.

The-Azzizia-desalination-plant-in-Al-Khobar-Eastern-Province-Saudi-Arabia-is-one-of-the-country’s-many-fossil-fuel–powered-desalination-facilities. (Photo courtesy Flickr user Waleed Alzuhair)

Pathway to a More Water-Secure Future

Going forward, populations across the Muslim world contending with serious water scarcity, will have to use a patchwork approach to address this unprecedented challenge. While desalination should be used as one tool, the emphasis must be placed on more efficient water management and finding ways to incentivize water conservation at every level of society, from individual households to big industrial firms and agricultural operations. Only by reducing demand for water, can water-stressed populations truly gain the upper-hand in the fight against scarcity of this vital resource.

Nevertheless, solar-power desalination could one day play a potentially influential role in shaping the Muslim world’s water future. Throughout many Muslim countries, the greatest concentrations of populations live in urban areas near or on a coastline, meaning desalinated water could be delivered to consumers without the need for costly and energy-consuming long-distance pipelines. Even populations living far from the ocean — including entirely landlocked nations — might stand to benefit from solar-powered desalination. “In countries where sea coasts are not available,” Moustafa Hatem Sewelam, an engineering manager with a Saudi desalination firm GETCO, told me recently via e-mail, “this technology can be used [to purify] brackish waters in desert areas.”

There are other hopeful signs as well. Costs of desalination technology are expected to gradually drop — as they have during the past several decades — thanks to improvements in reverse osmosis filtering technology, which makes the seawater purification process more energy efficient. As energy requirements are reduced, it becomes more likely, solar power will be able to provide sufficient energy for the purification process.

In the coming years, the eyes of many desalination experts will be focused on the outcome of the ambitious experiments now underway, on the coasts of Saudi Arabia and the UAE. “The experiences gained will help these countries and many communities in the world in need of suitable potable water,” predicts Anwar Ahsan.

Solar-powered desalination — with its potential to someday ease water stress in the most water-scarce corners of the world — indeed carries great promise. If the concept of harnessing the power of virtually unlimited sunlight to produce fresh water from a virtually unlimited supply of seawater should eventually prove viable scientifically and economically, the Muslim world will have a unique and historic opportunity in the decades ahead to become global pioneers in solar-powered desalination, finding themselves in an enviable position to disseminate this hybrid technology to water-stressed coastal populations around the globe.

Solar-powered desalination could one day emerge as a key part of the puzzle in mitigating the world’s worsening fresh water crisis. Photo courtesy of Flickr user Andrea de Poda.

Russell Sticklor (CGIAR/International Water Management Institute) is a water specialist and journalist covering the intersection of environmental change, population growth, and human security. He is a Non-Resident Research Fellow with the Stimson Center Environmental Security Program and co-author of “Water Challenges and Cooperative Response in the Middle East and North Africa” (Brookings, 2012).

*Images are courtesy the writer

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