Osmotic Power

In a perfect world, all energy plants would create enormous amounts of cheap, clean, renewable energy. Though we do not live in a perfect world, companies are trying to make this a reality. The Norwegian company, Statkraft,opened the world's first osmotic plant just last Tuesday. Though this plant produces just enough energy to brew a pot of coffee, the potential is groundbreaking. Statkraft predicts that eventually half of Europe's power could be produced from osmotic power from the saltiness of the sea (Dillow). Sounds like an unbelievable claim, but how exactly does it work?

Saltwater and seawater are separated into two chambers which are separated by a polymer membrane that only freshwater can pass through. The seawater draws the freshwater through the membrane, creating pressure on the seawater side, which can be used to drive a turbine, which generates the energy. Though this plant is just a prototype, Starkraft hopes to create a more efficient membrane in order to transfer more pressure to the turbine without using substantial amounts of energy in the process. A full-size osmotic plant, about the size of a football field, according to Statkraft, will be able to produce enough energy to power 30,000 European households.

Osmotic plants can be built where ever there is an abundance of both freshwater and saltwater, and "run without producing noise pollution or polluting emissions and can be integrated into existing industrial zones, perhaps being installed within unused areas of existing buildings" (Ridden). According to Rasmus Hansson, head of WWF Norway, "Renewable energy investments must be made in developing countries, and osmosis is a good example of technology which could be used in developing nations. The climate crisis cannot be solved by market mechanisms, such as carbon-pricing alone, but the upside is that investments made in renewable and sustainable energy sources can become profitable very quickly." (Ridden).
I find the potential of osmotic power very intriguing, and am interested in how it will take off. I suppose we will have to wait until 2015, when Statkraft intends to build a full-scale plant.

sources:
Dillow, Clay. "World's First Osmotic Power Plant Goes Live in Norway." Popular Science (2009): n. pag. Web. 29 Nov 2009. <http://www.popsci.com/science/article/2009-11/worlds-first-osmotic-power-plant-goes-live-norway>.

Ridden, Paul. "The world's first osmotic power plant from Statkraft." Gizmag (2009): n. pag. Web. 29 Nov 2009. <http://www.gizmag.com/statkraft-osmotic-power/13451/>.

"Q&A Osmotic power." Statkraft. Statkraft, Web. 29 Nov 2009. <http://www.statkraft.com/energy-sources/osmotic-power/qa/>.