Nuclear-based solution to water scarcity makes headlines

There are communities on every continent running short of water, according to the United Nations.

Unfortunately, although our planet is swathed by oceans and seas, only a tiny fraction of Earth's water - about 2.5% - is fresh, and demand for drinking water is projected to exceed supply by trillions of cubic metres by 2030, according to BBC.

Desalination plants, which remove the salt from seawater, could help supply the freshwater needed.

However, these plants are considered among the most expensive ways of creating drinking water- as they pump large volumes across membranes at high pressure, which is an extremely energy-intensive process.

One radical solution could be using floating vessels equipped with desalination systems.

Powered by nuclear reactors, these vessels could travel to islands, or coastlines, struck by drought, bringing with them both clean drinking water and power.

"You could have them moving around on an intermittent basis, filling up tanks," says Mikal Bøe, chief executive of Core Power, which has come up with a design for this type of desalination plant.

It may sound far-fetched but the US Navy has provided desalination services during disasters in the past, with the help of its nuclear-powered ships, while Russia already has a floating nuclear power station designed to potentially power desalination facilities.

There are already around 20,000 desalination plants worldwide, almost all of which are onshore. The majority are located in Saudi Arabia, the United Arab Emirates and Kuwait, with others in countries including the UK, China, the US, Brazil, South Africa and Australia, to name a few.

But some engineers say it could be cheaper to position this desalination technology offshore, where the seawater can be more easily pumped aboard.

For decades, engineers have dreamed of building floating, nuclear-powered desalination systems.

Core Power wants to use a vessel very much like a small container ship, but stack containers on board filled with desalination technology. The nuclear reactor would then lie at the heart of this vessel providing the huge amount of power needed.

The firm's floating nuclear desalination vessels could have varying levels of power output, from five megawatts, up to around 70, Mr Bøe adds. At five megawatts of nuclear power, it could pump out 35,000 cubic metres - or 14 Olympic swimming pools' worth - of freshwater every day.

Ideas such as this, and Core Power's design are "promising", says Raya Al-Dadah, head of the Sustainable Energy Technology Laboratory at the University of Birmingham. However, floating desalination has both advantages and disadvantages, she says. There are still challenges in terms of pumping the desalinated water ashore and in finding a workforce with both offshore experience and desalination expertise.