Again, there's no solution good enough

See what I mean? No matter what we do, it won't be good enough to reverse the "damage" we're causing due to our evil usage of fossil fuels. Even if we can make this solution cheap enough, we might inadvertently chop up fish! Notice the word FEAR, which is a common theme in global warming advocacy.

The Associated Press: Oceans Eyed As New Energy Source:

Because the technology is still taking shape, it is too soon to say how much it might cost. But researchers hope to make it as cost-effective as fossil fuels. While the initial investment may be higher, the currents that drive the machinery are free.

There are still many unknowns and risks. One fear is the "Cuisinart effect": The spinning underwater blades could chop up fish and other creatures.