St. Petersburg Times
Special report
Video report
  • For their own good
    Fifty years ago, they were screwed-up kids sent to the Florida School for Boys to be straightened out. But now they are screwed-up men, scarred by the whippings they endured. Read the story and see a video and portrait gallery.
  • More video reports
Multimedia report
Print Email this storyEmail story Comment Letter to the editor
Fill out this form to email this article to a friend
Your name Your email
Friend's name Friend's email
Your message

Buoys could deliver energy

Years of testing will be needed to determine if the technology will work.

By CURTIS KRUEGER, Times Staff Writer
Published August 3, 2007

[Times photo | Curtis Krueger]
St. Petersburg is testing a device which can generate electricity. Eventually, scientists hope it could become a viable power-generating technology. Ron Perline and fellow scientists from SRI International devised technology which will be put on a buoy in Tampa Bay and used to generate electricity from sea waves.

ST. PETERSBURG - One part of the answer to Florida's energy problems could lie in what surrounds us: seawater.

Scientists in St. Petersburg have begun testing a new device that generates power from rising and falling waves.

Some call it an exciting prospect, even though it will take years of testing to learn whether the technology can become viable on a large scale.

"There could be nothing more ideal for Florida to be looking at than to use the ocean to identify alternative forms of generating electricity," St. Petersburg Mayor Rick Baker said at a news conference Thursday.

The wave-power device uses technology developed by Ron Pelrine and other scientists at SRI International, based in California. The nonprofit research firm opened a St. Petersburg division this year that works closely with the University of South Florida's College of Marine Science. A Japanese company, Hyper Drive Corp., is helping to finance the research and hopes to commercialize the technology.

Like solar and wind power, energy from ocean waves and currents is considered a potential alternative to fossil fuels.

Other companies are testing devices that look like underwater fans, turned by ocean currents, and giant floating pencils with hinges.

But the one in St. Petersburg is different. It uses an SRI technology called an "artificial muscle." The artificial muscle is a sheet of stretchy plastic, coated with a substance that conducts electricity.

The buoy-mounted muscle is shaped like a big Slinky. It stretches out when the buoy drops between waves, and contracts as the buoy rides back up onto a wave. The Slinky-shaped muscle gives off electricity when it contracts.

This power could be stored in batteries and used later.

How much power will the St. Petersburg buoy consistently generate? At the moment, up to a whopping 5 watts, less power than needed for a household light bulb.

But new technologies start slowly. If things go well, says Peter Marcotullio, SRI's director of business development, buoys could be developed that generate 1,000 watts of power. String together a thousand, and that's a serious amount of energy.

The ocean brims with energy, making it a huge potential source for human needs, said Rick Driscoll, who directs the Center of Excellence in Ocean Energy Technology at Florida Atlantic University. Driscoll is not involved in the SRI effort.

However, he said, harnessing the sea's energy is easier said than done because oceans create such a punishing environment for man-made technology. That makes any effort like this one a challenge, he said.

Wave-power devices generate more electricity in places with bigger waves, such as the Alaskan coast, or the U.S. Pacific coast, Driscoll said. So those locations might prove better places to deploy wave-power devices once they're perfected.

Marcotullio said one advantage of the SRI system is that it doesn't use complicated machinery such as hydraulic pistons that would need to be constantly inspected and replaced.

Referring to the Slinky-like action of the artificial muscle, SRI scientist Roy Kornbluh said, "This generator has all the mechanical complexity of a rubber band."

Times staff writer Curtis Krueger can be reached at or 727 893-8232.

[Last modified August 3, 2007, 00:10:00]

Share your thoughts on this story

[an error occurred while processing this directive]
Subscribe to the Times
Click here for daily delivery
of the St. Petersburg Times.

Email Newsletters