Future of Desalination in the Context of Water Security

Three general concerns with desalination are at present. First, it is expensive because of its high energy requirements. Second, is its environmental costs, especially in terms of brine disposal. The third is the carbon footprints of the construction and operation of desalination plants. For most locations, desalination is the most expensive form of producing new sources of water which could contribute to security. In September 2022, the Saline Water Conversion Corporation (SWCC) of Saudi Arabia and Global Water Intelligence (GWI) organized an international conference on the future of desalination, in Riyadh. The conference was timely since the issue of the future of desalination, or the broader issue of the future of the world’s waters and the role desalination plays, needs to be discussed much more seriously.

By Asit K. Biswas and Cecilia Tortajada, 2022. Article published in International Journal of Water Resources Development , Vol. 38, Number 6, pages 921–927 . DOI: 10.1080/07900627.2022.2138135

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Taxonomy

• Water Security
• Water Security
• Desalination
• Sea Water Desalinisation
• Sustainable Desalination

1 Comment

1. Dr. Biswas clearly points out the issues regarding desalination (and recycling) of water.

    

   It should additionally be pointed out that water distribution systems already lose significantly more to water main leakage than their most ambitious desalination or water recycling projects might generate.  (Currently AWWA studies indicate average losses of ~20%, but planned desalination projects would supply less than 10% of the required additional water, at very high costs.

    

   For example, the California Public Utility Commission determined that the delivered cost for water from conventional sources averages USD 793/acre-foot; desalinated water has an estimated average cost of USD 3,889/acre-foot (with a maximum of USD 5,400/acre-foot); and recycled water has an estimated average cost of USD 2,869/acre-foot (with a maximum of USD 5,800/acre-foot).

    

   Recovery of the water lost to water main leakage would be far less costly than putting the desalinated or recycled water into the water mains that continue to leak.  Not enough effort is being done on the very basic problem of minimizing water leakage losses.

    

   The California Department of Water Resources points out that a very major problem is the fact that the accuracy of large water main type metering systems are difficult to determine. 

    

   The solution is "obvious":  Simply build aerospace-grade flow calibration systems (+/- 0.05% uncertainty) on water main size scale.  It is do-able, and leak detection by metering zone leak detection by mass/volume balance would then be easier.

    

   The cost for establishing low uncertainty large water flow calibration systems suitable for leak detection would we less than several months water loss of many distribution companies.