Desalination a valuable resource in addressing water scarcity


Photo from TheLeader DotInfo, flickr

Tyler Chalfant | October 22nd, 2019

As fresh water becomes increasingly scarce, countries are relying on desalinating seawater to prevent a crisis. Desalination plants remove salt to make seawater clean and drinkable through a process known as reverse osmosis. 

Scientists predict that the effects of climate change, a growing population, and the depletion of groundwater resources place a quarter of the global population at risk of running out of water in the near future. This risk is especially high in the Middle East and North Africa, where many of the desalination plants are being built. Saudia Arabia, the global leader in desalination, accounts for about one-fifth of all production. 

Other affluent countries, including Australia, China, Spain, and the United States, have begun producing desalinated water in water-stressed areas. However, the cost has been prohibitive to many countries. Researchers are studying how to improve the process to make it more affordable and accessible. 

Desalinated seawater is an important resource, that currently accounts for about one percent of the world’s fresh water. But the process is not without environmental risks, including a brine byproduct that contains toxic treatment chemicals, as well as high amounts of salt. Desalination also requires large amounts of energy, and as a result adds to the burning of fossil fuels and contributes to greenhouse gas emissions. 

Scientists use solar energy to make salt water drinkable


The sun sets in the Pacific Ocean off the coast of California. Oceans cover approximately 70 percent of the earth’s surface. (Mike/Flickr)

Nick Fetty | April 28, 2015

Researchers at the Massachusetts Institute of Technology have discovered a way to make salt water drinkable using solar panels.

This innovation recently won first place for the U.S. Agency for International Development‘s  2015 Desal Prize because of its potential to provide clean drinking water for millions around the world. MIT and Jain Irrigation Systems came up with a photovoltaic-powered electrodialysis reversal (EDR) system which can desalinate water by “using electricity to pull charged particles out of the water.” Ultraviolet rays are then used to disinfect the water. The system functions using relatively low energy consumption in areas that may be off the grid.

The research team was awarded with $140,000 to continue their research. To be eligible for the prize money, designs had to be cost-effective, environmentally sustainable, and energy efficient. The system is capable of removing salt from 2,100 gallons of water within 24 hours. It is also capable of converting 90 percent of salt water into drinking water, compared to reserve-osmosis systems which purify 40 to 60 percent of water.

The researchers have been developing this technology across India since 2014. This filtration system is expected to alleviate water shortage issues in California and other drought-stricken parts of the developed world while improving living conditions in India and other underdeveloped parts of the world where clean water can be scarce.

“The water scarcity challenges facing India in the near future cannot be overstated. India has a huge population living on top of brackish water sources in regions that are water-scarce or about to become water-scarce,” said Susan Amrose, a civil and environmental engineering lecture at the University of California-Berkeley. “A solution with the potential to double recoverable water in an environment where water is becoming more precious by the day could have a huge impact.”