Global climate change and overpopulation are combining to threaten fresh water supplies. To avert vast shortages, scientists are trying new ways to desalt seawater to bring clean drinking supplies to communities all over the world.

While desalination technologies are advancing they still remain cost prohibitive. A number of methods now exist to purify saltwater that include solar power and fossil fuels. But nuclear energy might be a more efficient method of removing contamination and saltwater because it can do so efficiently and on a large-scale basis without adding to concerns over global warming.

"Desalination is an energy-intensive process," says Meenakshi Jain of CDM & Environmental Services and Positive Climate Care in India. In a story that ran in the Inderscience publication International Journal of Nuclear Desalination, he highlights the energy problem facing regions with little fresh water. "Over the long term, desalination with fossil energy sources would not be compatible with sustainable development; fossil fuel reserves are finite and must be conserved for other essential uses, whereas demands for desalted water would continue to increase. Nuclear energy seawater desalination has a tremendous potential for the production of freshwater."

Jain emphasizes that renewable energy sources could help ease water shortages. Wind, solar, and wave power may be used to generate electricity while also carrying out desalination. That, in turn, could have a significant impact on reducing potential increased greenhouse gas emissions.

Nearly 40 million cubic meters of desalted water are produced worldwide each day, says the International Atomic Energy Agency. Most of the facilities to do so are located in the Middle East and North Africa and they use fossil fuels to draw the steam or electricity they need to facilitate the process.

But as environmental concerns grow over greenhouse gas emissions and water needs rise, cleaner options that have large-scale applications are necessary. The need is paramount. The demand for drinking water grew six-fold in the 20th century and is expected to increase another 40 percent by 2025, according to the United Nations.

Nuclear energy is the most feasible method, the atomic agency adds. It points out that the technology of coupling nuclear energy and desalination plants already has taken hold in Japan and Kazakhstan, where commercial facilities have been operating since the 1970s. India is among countries seeking to expand the base of national and international experience through a demonstration plant it is building. Altogether, the agency is working with 20 nations to advance nuclear science and desalination.

Universal Issue

Access to fresh water supplies is a universal issue. The United States is grappling with the dilemma and so is Australia and France. But developing nations are having the toughest time. The problems are exacerbated because of the fears of global warming. In an interview with OnPoint, Paul Faeth, executive director the United Nations Foundation's Global Water Challenge said that about 1.1 billion people don't have access to water and another 2.6 billion don't have access to safe sanitation.

He adds that about a third of all countries now have water scarcity issues and that this level could rise to two-thirds in 20 years because of global warming. Climate change not only affects temperatures but it also impacts water and the hydrologic cycle, adds Faeth. "In those areas that are dry, it's going to be getting drier and wet areas getting wetter. So you have people who are vulnerable are the first ones who are going to be affected. And for those who don't have water now, they're facing the biggest challenge."

The Inderscience publication International Journal of Nuclear Desalination quotes scientists who say that solar, wind and wave power are not cost effective fuel sources in the effort to create potable water. At least one scientist there is quoted as saying that floating nuclear plants could help solve the problem. Such plants could be permitted to operate offshore and where there is a dense coastal population. They could be used to provide electricity and run a desalination plant with the excess heat.

It is estimated that a 300-megawatt nuclear plant would be required to drive a desalination facility with a capacity of 1 million cubic meters of potable water a day. That's enough water to support a population of between 3 or 4 million people. That same population would require between 4,000 and 6,000 megawatts of installed capacity to meet its electricity needs.

Cost, however, could be a deterrent. Experts say that it is at least five times more expensive to purify seawater than it is to treat fresh water. The environmental community says that the ideal solution -- at least in developed nations -- is to focus on efficiency and conservation. That's a concept brought home by the recent dry spell in the southeastern United States and the subsequent squabbles that have occurred among neighboring states there because of those shortages.

Authorities around the globe are making dire predictions. The affects of climate change and reduced access to safe drinking water supplies are on collision course -- something that would affect the well-being of billions of people all over the planet. Greater conservation and efficiencies are a must. But so are the development and implementation of clean technologies that can desalt seawater.


 

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