AFA researchers testing ocean waves for energy

Dec 31, 2007 - McClatchy-Tribune Regional News - Tom Roeder The Gazette, Colorado Springs, Colo.

Researchers at the Air Force Academy are developing an idea that could use ocean waves to meet much of the nation's energy needs.

The devices used to extract the energy look like the paddle wheels on river steamships of old, but with some new twists added by researcher Stefan Siegel along with aeronautics research center director Thomas McLaughlin. They envision submersible barges lined with the wheels that would be able to use the movement of ocean water to generate electricity and transmit it to shore over submerged cables.

"Wave energy has lots of potential," said Siegel, who is working with cadets to figure out the mind-boggling mathematics involved in accurately modeling the invention. "There is also a tremendous amount of it available."

Although the idea might seem more appropriate for the Naval Academy at Annapolis, Md., McLaughlin said the idea evolved out of experiments to see how air moved around cylindrical objects.

"Water is a fluid and so is air," said McLaughlin, whose department helps cadets get hands-on engineering experience by working on research projects.

The academy has attracted grants from the National Science Foundation to help pay for the research. Siegel said the idea hasn't created electricity yet, but it has generated a national buzz.

Key to the invention is the idea that the blades on the paddle wheels will act like wings and can be steered to deal with different sea conditions. They would also be designed to work in pairs that spin in opposite directions to cancel out the power of the waves against the submerged barge.

Scores of designs to generate electricity from ocean waves have already been tried with limited success. The main problem with moving water is it can rapidly change intensity and direction.

By submerging the generating plant and allowing it to move with the waves, though, Siegel thinks he has those problems licked.

The main reason ocean-based power is attractive is that 70 percent of the world's population lives within 100 miles of a sea.

"If I can use the wave power right off Los Angeles or San Francisco, I have tremendous savings in infrastructure," Siegel said.

And because moving water is so much heavier than air, its potential to generate electricity is up to 25 times greater than a wind farm of similar size, Siegel estimates.

Key to turning the idea into reality will be the work of cadets using the academy's aeronautics supercomputer to calculate how the water will flow over the paddle wheels. Minuscule changes to how the paddles are designed can make a huge difference in how much power could be extracted.

The academy's focus on real-world projects helps cadets problem-solve their way through engineering, a far tougher task than working out textbook solutions, McLaughlin said.

"By working side by side with them, they can see what we do when things don't work," he said.

It will take years of trial and error to transform a project like the seapowered generator to something that sends kilowatts to homes.

"This is applied research," Siegel said.

CONTACT THE WRITER: 636-0240 or tom.roeder@gazette.com