VORTICES....Via Mark Kleiman, researchers at the University of Michigan have created a wave-based system for generating electricity called VIVACE, or "vortex-induced vibrations for aquatic clean energy":
The new device, which has been inspired by the way fish swim, consists of a system of cylinders positioned horizontal to the water flow and attached to springs. As water flows past, the cylinder creates vortices, which push and pull the cylinder up and down. The mechanical energy in the vibrations is then converted into electricity.
....A "field" of cylinders built on the sea bed over a 1km by 1.5km area, and the height of a two-storey house, with a flow of just three knots, could generate enough power for around 100,000 homes....The scientists behind the technology, which has been developed in research funded by the US government, say that generating power in this way would potentially cost only around 3.5p per kilowatt hour, compared to about 4.5p for wind energy and between 10p and 31p for solar power. They say the technology would require up to 50 times less ocean acreage than wave power generation.
...."If we could harness 0.1 per cent of the energy in the ocean, we could support the energy needs of 15 billion people. In the English Channel, for example, there is a very strong current, so you produce a lot of power."
Well, why not? Vortex-induced vibrations generated enough power to destroy the Tacoma Narrows Bridge in 1940, so why not get something useful out of it?
Of course, claims like these pop up constantly, and there's no telling how well VIVACE will work until there's been a real-world test. That will happen next year, when the boffins plan to set up a small prototype in the Detroit River designed to generate 3 kilowatts of power. No word yet on an ocean floor test.