Ocean Robots That 'Feed' on Whale Food

Aug. 19, 2004 -- Scientists are figuring out how to use one of the tiniest creatures on the planet to generate a virtually endless supply of electricity that can power remote sensors scattered across the world's far-flung oceans

They call it "plankton power."

Most oceanographic sensors, used to detect everything from temperature changes to the sounds of remote earthquakes, are powered by batteries. But batteries exhaust their internal fuel and run down, and replacing them thousands of feet below the ocean surface, in very remote areas of the planet, is not only expensive. It's impractical, and in some cases, nearly impossible.

So thinking there has to be a better way, oceanographer Clare E. Reimers of Oregon State University began working several years ago with other scientists at the Naval Research Laboratory in Washington, D.C., to see if they could come up with a better idea.

If they could figure out how to provide a self-sustaining source of electricity for oceanographic vehicles, they could develop machines that could swim like a fish, prowling across the ocean for months, if not years. These mobile robots could collect data over wide areas that could add immeasurably to our understanding of such critical issues as changing global weather patterns.

But you can't do that with batteries. So to succeed, they would need to rely on a type of fuel that is abundant throughout the oceans. What might that be? Well, what do fish eat? Other fish. What do small organisms eat? Smaller organisms.

"Organic matter is the basic fuel of the ocean," says Reimers, who directs an interdisciplinary lab at OSU's Hatfield Marine Science Center in Newport, Ore.

A Digesting Fuel Cell

The researchers have already demonstrated that it is possible to use decaying organic matter to power fuel cells. Prototypes developed by several institutions that are participating in the project have been tested in Oregon's Yaquina Bay and in a deep-sea canyon off Monterey, Calif.