About 20% of the world’s population has no access to safe drinking water, and this number will increase as the population continues to grow and global freshwater sources continue to decline. The worst-affected areas are the arid and semiarid regions of Asia, the Middle East and North Africa.
UNESCO has reported that the freshwater shortfall worldwide will rise to 500 trillion gallons/yr by 2025. They expect water wars to break out in the near-future. The World Economic Forum says that shortage of fresh water may be the primary global threat in the next decade.
But 500 trillion gallons/year only requires about 1,500 seawater desalination plants like the ones being built in California and Saudi Arabia. At a billion dollars a pop, that’s a lot cheaper than war and starvation.
Unfortunately, we presently desalinate only 10 trillion gallons/year worldwide.
As reported in the Tri-City Herald and NYTimes, stock exchange mutual funds have even formed surrounding water scarcity and have done quite well, like the AllianzGI Global Water Fund. This fund has averaged almost 10% since 2010 compared to under 6% for its average peer fund. These companies mainly deliver, test and clean drinking water.
In California, the MegaDrought, that ended in 2017 ran for five years, severely straining water supplies, agricultural needs and wildlife. It clarified the need to build new desalination plants like every other modern arid population in the world. Most of Abu Dhabi’s gas-fired power plants provide electricity to their huge desalination plants that deliver over a billion gallons of drinking water a day, at about 40¢/gallon. And it tastes good, too, I’ve tried it.
California needs 30 large desalination plants to deal with future megadroughts. They did recently build one in Carlsbad, but it’s not nearly enough.
Desalination technologies are capable of treating water from a wide variety of sources, including brackish groundwater, surface water, seawater, and domestic and industrial wastewater. While the wastewater from desalination is itself problematic, MIT has developed a process to turn it into useful products.
The two main types of desalination are: