Desalination and the Solar Solution
Raed Bkayrat, First Solar, on the future of desal in the Middle East.
It is impossible to overstate the indispensable role water plays in our lives. It’s in our food, our cars, our homes, and in the air we breathe. Considering this, the challenges of water scarcity and energy availability have been pegged as the greatest problems threatening humanity. This is due to the fact that most, if not all, of the other problems could be either resolved or alleviated by the availability of affordable clean energy and water.
These are sentiments that resonate strongly in the Middle East. Studies suggest that, today, the average citizen in the region has access to a little over 1000m3 of renewable freshwater, as compared to a global average of over 7000m3. In fact, according to the World Bank, 14 of the world’s 20 most water-scarce countries are in the Middle East and North Africa (MENA) region. These countries are also fortunate enough to receive some of the highest levels of solar irradiance on the planet and possess good access to the sea.
To meet the rising water demands in a region that is typically arid, governments have turned to large scale desalination and wastewater treatment. Notably, the MENA region accounts for about 38 percent of global desalination capacity; the United Arab Emirates is the second largest producer of desalinated water in the world.
Desalination is typically the process of seawater or brackish water separation into a freshwater component and a brine concentrate. Desalination methods are predominantly of two types – thermal desalination which uses heat to vaporize freshwater, and membrane desalination or reverse osmosis (RO), which makes use of high pressure to separate freshwater from seawater, using a membrane. RO is now a mainstream desalination technique, primarily because it’s more energy efficient than thermal, requiring only electricity to operate, while thermal also requires heat in addition to electricity.
In fact, the desalination process, by nature, is highly energy-intensive; in RO systems, energy consumption can account for almost 30% of the cost of desalinated water. Furthermore, if desalination is powered by hydrocarbons, as is the case in the Middle East, the opportunity cost – the economic value difference between domestically consuming fossil-fuels and exporting them internationally – is significant. Additionally, there is the significant environmental impact of burning fossil fuel on the scale that desalination and other methods of water treatment require. The point being that, simply relying on conventional energy sources for desalination cannot be a sustainable model, given the substantial economic and environmental costs involved.
It then comes as no surprise that a rising number of Middle Eastern nations are exploring the potential of solar energy as a solution to the region’s energy challenges, especially for desalination and water treatment. Solar can reliably complement conventional energy sources – particularly, in terms of addressing peak energy needs, or peak load shaving – and help offset the use of conventional fuels for domestic consumption, thus freeing hydrocarbons for export and reducing reliance on imports. Additionally, there is a significant decrease in operational and maintenance costs of plants, primarily due to the fact that minimal water and almost no fuel is required to generate solar energy. Finally, solar is a clean and renewable energy source which ensures that greenhouse gas emissions are kept to a bare minimum.
Despite the obvious benefits, in the Middle East, less than 1% of total desalinated water is produced using renewable sources. However, as efficiencies, reliabilities, and economies improve; policymakers across the region are earmarking investment and committing to large scale renewable desalination projects. The Middle East today has an opportunity to set a global benchmark for solar-powered desalination.
Dr. Raed Bkayrat is Vice President, Business Development, Middle East and Saudi Arabia for First Solar and Research Director at (MESIA)