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10 surprisingly easy sources of alternative energy

By: Bryan Nelson on Nov. 30, 2009, 11:27 a.m.
Saltwater Power or Blue Energy

Photo: rachel_thecat/Flickr

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Saltwater power

It has been called saltwater power, osmotic power or blue energy, and it is one of the most promising new sources of renewable power not yet fully tapped. Just as it takes huge amounts of energy to desalinate water, energy is generated when the reverse happens and saltwater is added to freshwater. Through a process called reverse electrodialysis, blue energy powerplants could capture this energy as it is released naturally in estuaries around the world.