Osmosis is the tendency of dissimilar fluids, like fresh water and salt water, to blend across a barrier. That force seems small, but researchers have been able to demonstrate that the force is measurable, and the creation of the correct membrane or barrier can extract electricity from the osmotic forces. This is a discovery, which is another way of saying it is a long way from being widely used. The surprise, however, is that osmotic power can be much more powerful than solar power.
“The results suggest that with the right salt gradient, you could get a power density of 106 W/m2. For comparison, the amount of energy we get from the Sun maxes out at about 1,000 W/m2.” – Ars Technica
Translated from math into English, osmosis can generate 1,000 times more energy than solar power; and can do so regardless of weather, time of day, or any of the other interruptions that cause cautions about most renewable energy sources. This discovery is so early that they haven’t even conjectured about how long it will take to implement such a system; but it is a great example of solutions yet to be uncovered.
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