Its all about Paper...

Why is there drought when we're surrounded by water?

The problem is that the desalination of water requires a lot of energy. Salt dissolves very easily in water, forming strong chemical bonds, and those bonds are difficult to break. Energy and the technology to desalinate water are both expensive, and this means that desalinating water can be pretty costly.

It's hard to put an exact dollar figure on desalination—this number varies wildly from place to place, based on labor and energy costs, land prices, financial agreements, and even the salt content of the water. It can cost from just under $1 to well over $2 to produce one cubic meter (264 gallons) of desalted water from the ocean. That's about as much as two people in the U.S. typically go through in a day at home.

But switch the source to a river or an aquifer, and the cost of a cubic meter of water can plummet to 10 to 20 cents, and farmers often pay far less.

That means it's still almost always cheaper to use local freshwater than to desalinate seawater. This price gap, however, is closing. For example, meeting growing demand by finding a new source of water or by building a new dam in a place like California could cost up to 60 cents per cubic meter of water.

And sometimes these traditional means of “harvesting” water are no longer available. As such, this cost figure is expected to continue to rise, which is why California is now seriously considering desalination and why the city of Tampa, Fla., decided to build the biggest desalination plant in the U.S.

The International Desalination Association says that as of 2007 there were about 13,000 desalination plants operating around the world. They pumped out approximately 14.7 billion gallons (55.6 billion liters) of drinkable freshwater a day. A lot of these plants are in countries like Saudi Arabia, where energy from oil is cheap but water is scarce.


So how is energy used to separate salt from water?

There are two basic methods for breaking the bonds in saltwater: thermal distillation and membrane separation. Thermal distillation involves heat: Boiling water turns it into vapor—leaving the salt behind—that is collected and condensed back into water by cooling it down.

The most common type of membrane separation is called reverse osmosis. Seawater is forced through a semipermeable membrane that separates salt from water. Because the technology typically requires less energy than thermal distillation, most new plants, like Tampa's, now use reverse osmosis.

www.scientificamerican.com...

Apparently its not cool to upset the fishes either....

There are environmental costs of desalination, as well. Sea life can get sucked into desalination plants, killing small ocean creatures like baby fish and plankton, upsetting the food chain.

It's 2014 people... why isn't water free?

I call bullcrap. It wouldn't take a large sum of money to desalinate seawater. Its called turning water into steam. The Sun shines every single day. Why not use that free energy source to create salt free water? Imagine a world without money. People would do things not because they get paid, but because they truly want to. No one starves because they can't afford to pay. If its free for some, it should be free for all. The future of this world will be without currency.

reply to post by Oannes


Considering without water everything on this planet dies....

but I guess it costs too much to keep our species alive these days...

reply to post by Akragon

It's 2014 people... why isn't water free?

water is free , its the delivery of treated water that you are paying for