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Critics say offshore wind turbines, like these giant propellers newly installed off the coast of Ireland, are eyesores and endanger wildlife.

Wind Power Reconsidered

Innovations and steep gas prices may at last kick-start wind energy in the U.S.

By Joshua Tompkins

The U.S. has zero. Several have been proposed along the wind-whipped East Coast, but if the hurdles faced by the planned 420-megawatt Cape Wind installation off Cape Cod are any indication, windmills won’t be dotting U.S. coastlines anytime soon. Many local residents and officials—including Senator Ted Kennedy—say that the spinning propellers, anchored in the seabed six miles out, would spoil the view, impede navigation, and threaten birds. “We’re probably going to see controversy over any offshore site,” says Tom Gray, deputy executive director of the American Wind Energy Association.

Meanwhile the nation possesses practically boundless land-based wind resources that it’s only begun to tap. Wind farms in 30 states currently provide less than 1 percent of the nation’s total electricity demand, but according to the U.S. Department of Energy, there’s enough harvestable wind to light up the whole country. The actual goal of the wind energy industry is less lofty yet still ambitious: to supply 100 gigawatts (about 10 percent of the projected national capacity) by 2020.

Hitting that number will require not just harnessing more of the stiff 18-to-20mph winds that whistle through Rocky Mountain states but also the lighter 12-to-18mph breezes that sweep across vast swaths of the Great Plains and upper Midwest. Wind energy firms are developing efficient turbines that use multiple generators and strong, lightweight carbon-fiber or carbon-glass-hybrid rotor blades. Such upgrades will result in higher output wattage and lower production costs—and the latter are already on par with natural gas–burning power plants. (Solar power still costs several times as much.)

But the real limit to wind power expansion isn’t the turbine output; it’s the proximity to the power grid, experts say. Countless remote locations that possess good wind lie far off the grid, leaving wind farm developers, governments and utility companies to squabble over who will pick up the tab to string a high-voltage connection to civilization. “If the first 50-megawatt wind farm to go into Nebraska has to pay for the cost of the transmission line to Chicago, then it’s not going to get built,” Gray observes.

Right now, virtually nothing is being built while companies await the renewal of the federal Production Tax Credit, which provides key incentives to green-power developers. It expired late last year, and if Congress renews it this fall, projects in various states totaling at least 2,000 megawatts are slated to break ground. The largest, a 310-megawatt installation planned for two sites in northern Iowa, will be the biggest land-based wind farm in the world.

Offshore, there’s no limit to what could be set up once developers devise a stable, economical deep-water platform—possibly tethered to the ocean bottom—that could be placed far out at sea, where the neighbors won’t complain and an estimated 900 gigawatts’ worth of air power begs to be harvested. Robert Thresher, director of the Department of Energy’s National Wind Technology Center, thinks a workable system is less than a decade away. Transferring energy to shore could be costly, but “the technology’s doable,” he says.

The Skystream home windmill starts cranking out electricity in scant 8mph winds. Its 12-foot-long blades allow it to hit maximum output (1.7 kilowatts, 30 to 90 percent of most homes’ needs) at 20 mph and keep its noise on par with an air conditioner. Installation is easy, with all electrical parts contained in the turbine body. And you can sell extra watts to your utility company to fund that solar-panel project. About $10,000; windenergy.com

Comparison of Wind Power Technologies

Wind turbines important for area's future energy needs

Heather Coit

A haze covers he wind farm as seem from the sky outside Ellsworth. The $700 million project is expected to be completed by year's end.

 

The rolling landscape around the small town of Arrowsmith – about 14 miles west of Gibson City – looks more like Holland than central Illinois.

Some 50 square miles of prime black farmland are dotted with windmills.

As gusts of wind blow over the corn and soybean fields, giant turbines convert the energy it creates into electricity. Each tower is 258 feet tall – taller than a 20-story building – with 8-foot-deep foundations.

When the Twin Groves Wind Farm is completed in December, it will become the second-largest wind farm in the country, with 240 turbines. The largest is the Horse Hollow Wind Energy Center near Abilene, Texas.

The $700 million farm is being developed by Horizon Wind Energy of Houston.

Twin Groves is expected to produce 400 megawatts, enough to provide power for 120,000 homes.

"I believe wind farms have the potential to be the future for energy here in the United States," said Mahomet resident Alvin Cargill, who serves as quality control manager for the farm.

Cargill said the turbines can generate electricity as long as the winds are blowing at between 12 and 55 mph.

Sensors at the top of each tower measure wind speed and direction.

If the winds blow at less than 12 mph, the turbines won't turn fast enough to make electricity. The turbines produce a maximum amount of electricity from 22 to 55 mph.

"The turbines automatically turn off when the winds exceed 55 mph and then will resume operations when the winds come back down again," Cargill said.

Cargill, 48, moved to Mahomet when he was hired to work on the project.

"I've got an RV, and Mahomet has one of the few RV parks that is open all year round," Cargill said. "Besides, Mahomet is a terrific community. I can't think of a better place around here to live."

Cargill said Horizon chose the Arrowsmith region because the land there is both flat and elevated, making the moraine ideal for capturing winds. In addition, a major electricity transporting line owned by Commonwealth Edison runs near the site.

Each turbine has an international flavor to it. While the tower sections were made in Shreveport, La., the blades came from Spain, and the hubs and cells were built in Denmark.

"Here's how it works," Cargill said. "The wind pushes the turbines. Each turbine has a transformer that catches electricity generated by the site.

"Underground lines buried 4 feet deep below the ground send the electricity to a substation. The substation then takes the electricity out to the grid."

Cargill said fiberoptic lines allow Horizon employees to control the operation of each turbine remotely from an operations and maintenance building on Illinois 9 and from Horizon headquarters in Houston.

"A farmhouse is being renovated to create some office space," Cargill said. "It will be like a visitor center, a place you can go to learn more about the technology."

While the electricity is distributed through Commonwealth Edison's transmission lines, Cargill said, Horizon can sell its wind electricity to anybody.

Cargill's job involves inspecting the 50 miles of roads that were built specifically for the project and the turbines themselves. About 220 to 250 people have worked on Twin Groves since June 2006.

Cargill and his wife, Carla, formed their own company, Turbine & Tower Enviro-Clean, which will provide portable washing crews to clean turbines at wind farms.

Their daughter, Mendie, leads one of the washing crews.

"There are three ways you can clean them," Cargill said. "You can clean them by rappelling. You can clean them with a pressure washer. You can clean them with a crane."

Cargill said his favorite time of day is in the early evening, when he can watch the windmills turn over the corn fields of Arrowsmith.

"When they start running, they are very relaxing," he said. "I like to sit and watch them."

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