Will the anaconda or the oyster rule wave power?

FROM giant hydraulic oysters that sit on the sea floor, to long rubber snakes that writhe in the ocean swell, there's no shortage of creatures designed to harness the power of the waves. If wave power is to emerge as a viable form of green energy, we need to put them to the test and only the most reliable can expect to survive.

While there's a veritable menagerie of strange beasts taking to the sea, most of them can expect a humdrum life, says John Chaplin, a marine engineer at the University of Southampton in the UK. "The fundamental problem facing wave-power devices is that most of the time the water is moving with rather low velocities," he says.

Just as wind turbines grind to a halt on a quiet day, wave power machines generate little power in quiescent conditions. That's the challenge for wave power - how to extract energy from lifeless waters. "Such a wide-open brief has led to an enormous range of inventions," says Chaplin.

Budding wave-power designers are getting ample opportunity to find ways to turn gently bobbing waves into energy, with new projects hitting the water with metronomic regularity. For example, last month, New Jersey-based Ocean Power Technologies confirmed it was to start work on a project to deploy 10 of its PowerBuoy machines 4 kilometres off the coast of Reedsport, Oregon. They ride on the surface, converting the up-and-down motion of the waves into electrical power.

This project and others like it will add to the growing throng of wave-power systems already in the water.