Wind is the New Oil

The construction of the Taconite Ridge Wind Farm

Chris Godsey

Minntac looms enormous in the distance as Minnesota Highway 53 north drops from Eveleth toward Virginia and Mountain Iron. For decades, the U.S. Steel taconite mine and pellet plant dominated the horizon; last August, though, wind turbines—each one 260 feet tall and bearing three, 153-foot blades—started growing out of that same horizon’s earth. The turbines have transformed one of the Iron Range’s iconic horizons, and the turbines seem like the first in many inevitable steps toward more renewable energy.

Now ten strong across the sky, the almost impossibly huge turbines comprise the Taconite Ridge Wind Energy Center, the first commercial facility of its kind in northeastern Minnesota. Minnesota Power (under the aegis of its parent company ALLETE) owns the wind farm, which sits on U.S. Steel land near Minntac. At full capacity, the turbines are expected to provide 25 megawatts (Mw) of electricity—enough to serve 10,000 homes.

In fundamental ways, this wind farm project that got underway in August 2007 and was completed this past June is about adding new facets to familiar experiences. It only makes sense, then, that two of Taconite Ridge’s leaders are young men working within venerable institutions.

Dan Janisch, 32, managed Taconite Ridge construction for primary contractor Krauss-Anderson of Duluth. UMD electrical and computer engineering graduate Andy Remus, 31, is Minnesota Power’s Taconite Ridge site manager. They’re seriously competent guys—why else would they have been asked to lead such an enormous project?—so they can walk the talk of kilovolt reinversion, multi-agency permitting, and other concepts complicated enough to strain most people’s brains.

They’re also engaging, easy to chat with, and able to describe the wind farm’s complicated construction and operation in terms accessible to folks without rarified knowledge. And every now and then, especially when they’re discussing one of the project’s more exciting aspects, they break out into big smiles and exude charming enthusiasm.

Good idea. But where to put it?

Minnesota Power studied the region for a couple of years to find feasible wind-farm locations.

“Taconite Ridge is built on a rock ridge,” says Jansich, who worked on a few wind power projects after earning his construction management degree from the University of Wisconsin-Stout. “That’s not unusual, but it’s challenging.”

“The site works well,” Remus adds, “because there’s no mineable material beneath it, it’s close to a Minnesota Power connection facility, and it yielded a good outcome in wind studies.”

Once Minnesota Power had worked out an agreement with U.S. Steel, Janisch, his wife, Lisa, who was Krauss-Anderson’s superintendent for the project, and Remus had a lot of permitting and site-preparation work to coordinate.

“It was a huge task,” Remus said with a smile. “I was responsible for Minnesota Power’s interface among contractors, sub-contractors, Minntac, and all other entities. We still need to coordinate activities with Minntac’s work—maintaining communication with them was very important, and it’s gone very well.

“We had deliveries every day, and we couldn’t let what we were doing impact them—they don’t want a 90-foot tower section sitting in the middle of their gate, snarling up traffic during huge shift changes.”

As Krauss-Anderson’s project manager, Janisch says, he typically dealt with the overall schedule, budget, and coordination of all contractors and their associated contracts.”

Lisa Janisch, as project superintendent, handled field coordination and day-to-day scheduling.  Superintendents also play an enormous role in safety and quality control, as they are on site 100 percent of the time.

  “I got to go to a Public Utility Commission meeting in St. Paul,” said Janisch. “I thought that was neat, but I enjoy logistics and planning more than some people might. We worked around wetlands and other sensitive areas with help from the Army Corps of Engineers. We had cultural assessments performed—it was an unmined ridge, but there was potential for finding remnants of logging, mining, trapping, and other activity that has cultural and historical significance to the area. What we wound up finding was a lot of mud.”

By the time winter hit, roads were in and holes were blasted, dug, and filled with bases.

“We had a lot of logging to do,” Jansich said. “We took down the minimum number of trees possible—it’s just more work and environmental impact to take more than is necessary—but we did need a certain amount of room to assemble the turbines.”

Each turbine sits on a hexagonal base that’s 10 feet deep, 52 feet across, and supported by a dense skeleton of steel rebar. Some base holes had to be blasted out of the rock that lies just under much of the Iron Range’s surface.

Hollow areas in the bases’ centers allow cables that carry electricity from each turbine’s generators to pass down through the towers and underground to a sub-station and eventually to the toasters, lamps and big screen televisions of MN Power customers.

During spring and summer, the turbine tower sections, rotors, blades, gearboxes, and other parts were delivered, assembled, and meticulously tested, re-tested, then tested again.

“They all go through what’s called a commissioning process,” says Remus. “We verify connections through a specific process from the bottom to the top. That process went fairly well. Weather didn’t cooperate sometimes, but everything looks good.”

All ten turbines went online together for the first time on the evening of Monday, July 22.

“That was pretty much a milestone,” Remus said over a plate of Perkins French toast the next morning, his obvious excitement barely contained behind a broad grin.

One problem, ironically enough, was the wind.

Everyone who worked on building the farm had direct experience or was trained in specific aspects of turbine transportation and construction.

“One of the cranes we used was a 440-ton crawler crane that requires a specialized operator,” said Janisch. “Using equipment like that is not a good time to learn. Our heavy-haul drivers had transported turbine parts before—the parts are big enough that they require specific trailers with steerable rear axles. Wind power is becoming popular enough that those drivers spend most of their time just hauling turbine parts.”

Janisch said each piece typically took 20 minutes to lift and place.

“We’d go as fast as we could,” he said, “to avoid the wind. We typically worked 10- or 12-hour days. There was a lot of waiting on the weather. We actually had specialized forecasting equipment so we could know whether keep people waiting around.”

Both Jansich and Remus said the same factors that make the Taconite Ridge site viable for generating power—consistent and unobstructed wind—also made it a difficult construction site.

“It’s kind of a catch-22,” said Remus. “Weather was a huge factor. We battled a lot of rain, wind, and snow. It’s tough to build a wind farm on a windy site.”

From where the bottom tower piece attaches to its base with nearly 150 huge bolts concrete-embedded bolts topped with nuts to match, all of a turbine’s parts are fastened with hardware tightened to exacting torque specifications. Once the turbines are assembled, their function is almost incomprehensible.

“Each turbine is three rotor diameters [306 feet] from the others,” says Janisch. “Each one is outfitted with a ultrasonic wind vane and anemometer, and based on the readings from those instruments it can adjust its rotor and blades to most efficiently catch the wind.

“The machines can also speak to each other; if wind is coming straight down the array, they an adjust so there’s no dead spot because the first turbine is catching all the wind and creating a wake behind it. They can also be monitored and controlled remotely.”

An on-site, 4,000-square-foot maintenance operations is exclusively powered by the turbines, says Remus. “It will be LEED certified—we’re aiming for a silver certificate.” (LEED is an acronym for Leadership in Energy and Environmental Design, a building-rating system developed by the U.S. Green Building Council.)

“The turbines get maintained at regular intervals,” says Janisch. “Parts need to be tightened, lubed, and inspected every so often. A four-person maintenance crew will be at the site full-time.”

Remus said it’s “a surreal feeling” to drive into Virginia and see the turbines arrayed along the ridge in the distance. “Especially after seeing the conceptual video,” he said, “to see them in reality is really something.”

He also seems excited about potential for future wind projects on the Iron Range.

“I think there’s more opportunity up there,” he said. “Feasibility and capacity studies are going on right now.”

Stay tuned. Wind just might be the Iron Range’s new iron ore.