Potential of ocean
waves a siren call
for energy
engineers
The ocean shows Lei Zuo, associate professor
of mechanical engineering, the potential for abundant cheap, clean energy.
In the United States, where 53 percent of the population lives within 50 miles of the coast, energy
potential from ocean waves could make up 64 percent of the electricity generated from all sources
in the country in 2010.
That potential has Zuo excited, and he’s not
alone. The U.S. Department of Energy (DOE) recently confirmed a $2 million grant for Zuo to produce a prototype new generation of ocean wave
generator.
“Virginia Tech is the best in the nation in the
fields of energy harvesting and power electronics,” he said. The current project with DOE will see
Zuo teamed with professors Robert Parker from
mechanical engineering and Khai Ngo, the Bradley
Department of Electrical and Computer Engineering at Virginia Tech; the National Renewable Energy Laboratory in Golden, Colorado; the Resolute
Marine Energy company; and THK North America.
The innovation at the heart of Zuo’s plan, is the
Mechanical Motion Rectifier, a novel power takeoff that uses the up and down and back and forth
oscillation of wave energy and turns it into a
unidirectional rotation to drive the generator. The
design, which also uses a ball screw and highly efficient power electronics, will be placed in a metal
or composite housing, which is placed in the water in the same way as a buoy. Energy generation
begins almost immediately as the waves move the
buoy and the components inside.
Compared to other renewables, ocean wave energy generates greater returns. A square meter of
solar gives about 1.5 kilowatts; a square meter of
wind generates about one kilowatt; and a meter of
ocean wave front, power generation can be between 10 and 100 kilowatts.