On the roof of Cleveland State University’s plant-services building, four wind turbines hang off the side of a 20-by-25-foot cylinder. A large motorized truss atop the cylinder turns them toward the wind every few minutes. Another turbine spins slowly nearby. It’s the control that will determine whether the setup is the forbearer of a renewable energy revolution or a $400,000 method for scaring birds away from water towers.
“Make sure you point out in your story how the control turbine isn’t
spinning,” says Dr. Majid Rashidi, builder of this elaborate
experiment.
The control turbine isn’t spinning, but the other four, attached to
the cylinder, are whirling away. “The cylinder basically amplifies the
energy,” Rashidi explains, “It makes the turbines happier.”
And happy turbines produce more power.
A Clevelander for 31 years, Dr. Rashidi earned his Ph.D in
mechanical engineering from Case Western Reserve University in 1987,
and after a brief stint at NASA’s Glenn Research Center (back when it
was the Lewis Research Center), he began teaching at CSU. After 22
years of teaching, he’s now chairman of the engineering technology
department. Armed with $1.5 million of funding from the state of Ohio
and the U.S. Department of Energy, he’s been working hard on this
prototype since 2005.
As wind hits the cylinder, it’s forced around the sides, amplifying
the wind velocity around it by roughly 1.8 times. A computer system
measures wind direction and controls a motor that adjusts the turbines
automatically to catch it. In theory, this should result in turbines
that produce as much as four times more energy than normal. According
to Rashidi, the turbines each generate about two kilowatts of
electricity. Together, the prototype’s four turbines generate enough
electricity to power eight typical households.
Of course, it’s still a theory. As the wind flies in from constantly
changing directions, the system isn’t always able to adjust itself
quickly enough. There are awkward moments when the control is spinning
wildly while the tower sits still, waiting to be reoriented. Rashidi
admits there were still some kinks in the prototype’s computer system,
but project manager Jon Erdmann reported later that the problems had
been sorted out.
“There’s really no rulebook that says, ‘This is how you chase the
wind’,” says Erdmann. “When you’re inventing something, you have to
expect there to be some kinks to work out.”
With the tower in working order, the next step is to begin
collecting a year of constant data to prove the concept’s validity. “So
far, I’m very pleased with the results,” says Rashidi.
Rashidi’s concept is hardly the first design to generate that level
of wind-energy production. But what sets it apart from the dozens of
other prototypes in the high-hype renewable-energy market is its
potential in the urban environment. Most turbine designs, like the
massive one in front of the Great Lakes Science Center, are impractical
for city use because of their size. He calls this prototype a “design
evolution” — more compact and affordable than previous
turbines.
The sprawl of large buildings in cities usually cuts wind speed
below what’s necessary to create wind energy affordably. Plus,
Rashidi’s cylinder nearly doubles the velocity of the wind, making
turbines effective in areas with much lower wind speed. The turbines
are smaller too. Each turbine is about 7 feet in diameter —
compared to the 88-foot turbine standing in front of the science center
— allowing them to be installed on buildings without the danger
and cost of other designs. Making it even more affordable, Rashidi
points out that the cityscape is riddled with cylinders like water
towers, chimneys and silos, just waiting to have his turbines strapped
alongside them.
The idea isn’t just to cover Cleveland in wind turbines, but to
produce them here as well. Every part of the project was created in
Cleveland except the turbines themselves, and there’s no reason why
they can’t be made in town as well.
“I hope this creates some kind of economic impact in Cleveland and
Northeast Ohio,” says Rashidi.
There is talk that Rashidi is planning to install at least one more
wind turbine in the city. According to Erdmann, the next project will
be based on Rashidi’s earlier design — a 15-foot wide spiraling
tower with multiple turbines placed on it. Those involved aren’t ready
to make the location public yet but have described the site as
“extremely high-profile.”
This article appears in Jul 8-14, 2009.