Wyoming weather challenges wind project

Duke Energy’s Top of the World wind power project in Wyoming faced some severe weather challenges—with minus 30 degree temperatures—and an inflexible deadline for getting material to the site, due to an Interstate bridge construction project. But the project was completed on time.

By Paul MacDonald

The past year was a busy time for wind power projects for major utility Duke Energy.

In fact, the company was so active with projects that it will soon be hitting a milestone: 1,000 MW of wind power under production. Pretty good, considering the company has only been involved with wind power in a big way for a few years. In late November, the company brought the 51 MW Kit Carson wind power project in Colorado online, giving it 986 MW of wind capacity at nine wind farms in four states—Wyoming, Texas, Pennsylvania, and Colorado.

Since 2007, Duke Energy has committed some $1.5 billion to build its wind power business. “The remarkable growth of our commercial wind energy unit over the last three years illustrates our commitment to building a significant emissions-free power generation business,” says Keith Trent, president of Duke Energy’s commercial business.

A big contributor to moving toward that 1,000 MW benchmark was the completion this past fall of the 200 MW Top of the World wind project, in Wyoming, the second largest wind power project the company has ever built. It is also the largest wind farm Duke has built in the state. The company now has four wind farms in Wyoming.

The project supplies wind energy to regional utility Rocky Mountain Power under a 20-year Power Purchase Agreement. Rocky Mountain now has 1,100 MW of wind power, and the company says it is on track to achieve their objective of having 2,000 MW of renewable power in place by 2013.

The Top of the World location has a number of clear advantages that made it a prime site for development, says project manager David Grogg.

“One of the advantages is that it was close to a point of interconnect that allows us to easily connect into the grid,” says Grogg. “When it comes down to it, you can generate wind energy almost anywhere there is wind, but it makes it economically challenging if you need to have a very long transmission line.”

There is indeed good wind at Top of the World. “Top of the World is viable in terms of our economic model—the wind blows at a rate and consistency that can support a project for 20 to 25 years,” notes Grogg.

A third major advantage—and a valuable advantage at that, in a time of NIMBY-ism—is that the project has local support.

Additionally, Wyoming is an attractive state for wind development, though that may change in the future due to new tax regulations (see sidebar story on page 28).

Top of the World is indeed a massive project, being located on 17,000 acres of private land under lease in Converse County, in the eastern part of the state. The nearest major center is the city of Casper, just to the west. Most of the land for the site is used for sheep and cattle ranching. There is also a fair bit of hunting that goes on.

As developer of the project, Duke Energy had to deal with only four landowners in negotiating land leases. The landowners viewed the project positively, seeing it as an additional source of revenue in addition to the ranching and hunting activities—and the fact that a wind farm would not interfere with either.

The wind project also means that landowners can now have better access to their large acreages. “We developed a road system as part of the project,” Grogg noted. “So not only do the landowners get the benefit of the revenue from the project, they can now penetrate deeper into their land more easily. They can ride into their land on a road, instead of just a two-track. It’s mutually beneficial for both of us.”

With the large size of the Top of the World site, they developed nearly 30 miles of road. “That road had to accommodate a very large crane and heavy truck traffic, but we reduced the footprint of the road once the project was complete, for pick-up traffic.”

Duke Energy tries to work closely with landowners in a number of aspects, Grogg says. When they are building roads on large pieces of property, such as Top of the World, if possible they will use quarries the landowners already have on site, purchasing aggregate used in roadbuilding. “If we can get rock on site, it saves us the transportation costs, and it also contributes financially to the landowners in yet another way.”

Getting all the 200 MW of wind components to the site was helped by the good transportation infrastructure in Wyoming. “The State has a strong rail network that allowed us to get the materials to a centralized point,” says Grogg. “We had a laydown yard, near the Casper Airport, to bring in the blades and the nacelles.” Having rail access was especially helpful since many of the components came from various parts of the U.S. and overseas. The nacelles for the GE turbine units, for example, came from North Carolina, and the blades for the Siemens turbines came from a new plant in Iowa.

	Duke Energy, Wanzek Construction, and Siemens employees proudly assemble beneath Tower 90 at the Top of the World Windpower project. One of the wind turbine blades atop Tower 90 was inspected by President Barack Obama at the Siemens manufacturing facility in Fort Madison, Iowa (see sidebar story on page 27).

This, and other major aspects of the Top of the World project, were covered by kind of a blanket legislative act in Wyoming, called the Industrial Siting Act. Applying to any project with a value of over $173 million, the act covers virtually all aspects of major projects, from transportation to the environment, the impact on local roads, and details such as where construction workers are going to live and how they are going to get to the work site.

One approach that Duke took to reducing the impact of the project was particularly interesting. Under the agreement, Duke took detailed before and after photographs of the roads that were used to transport equipment. If there was any damage to the road, Duke agreed to return it to its original condition. “We really felt that we owed it to the county or the state—if we damaged the road, we would fix it,” says Grogg.

They had some heavy loads on those roads; nacelles, for example, weighing in at 192,000 pounds.

As part of this process, Duke paid for a $100,000 asphalt patch at the entrance to the road to the wind farm, which received a good portion of heavy traffic.

Throughout the process, Grogg made himself very available to the Wyoming Department of Transportation (WYDOT) staff to answer any questions and settle any issues. He was, essentially, the point person for the project.

“They could phone me, email me, or ask me to come out, and they knew that I represented Duke, and they could count on what I said. I think that helped to expedite things.”

Overall, Grogg said that Wyoming’s Industrial Siting Act was helpful from both the planning and construction perspectives, in that it makes it clear what Duke Energy and its contractor on the project, Wanzek Construction, were expected to do.

The one unexpected aspect to the Top of the World project, as with all wind power construction projects, was the weather. As some of the residents say, Wyoming can get plenty of weather.

In Wyoming, roads and transmission lines can be built without a permit, so Wanzek Construction started in on both in early November 2009, in advance of receiving a project permit. As scheduled, they received the permit in January, so they were carrying out the prime part of construction in -30 degree temperatures. They had their share of weather days, when the project was shut down due to high winds or extreme cold.

“We know when our equipment can run, and when it shouldn’t be run—and when it gets too cold, we stop,” says Grogg, matter-of-factly.

The extreme weather did not end once winter drew to a close. They had a 25-year rain event in spring 2010. “There was an advantage to that, though,” explained Grogg. “We learned—real quickly—where the water was going to go and what controls to put into place.”

In terms of managing the overall project, each morning, representatives from Duke and Wanzek
Construction and any other contractors involved would have a POD (Plan of the Day) meeting that would define what was going to be happening that day.

“The first things we would talk about would be safety and any environmental matters. Then, depending on what was going on that day, we might talk about what hunting might be going on at the site by the landowners that day, where that was going to be, what they were driving, and whether we had to work in that area, and alert our people to what was going on and plan the appropriate safety measures.”

They would end the week with meetings, to ensure they were on schedule. Then there would be monthly meetings, which would involve a larger group of people including other Duke Energy representatives, from the head office in Charlotte, supplier representatives, and any other necessary parties.

WYDOT had a firm date for construction work on a bridge on the major Interstate highway, I-95, that led to the site. That work was starting August 1—no ifs, ands, or buts about it, which meant that all of the material for Top of the World had to be across the bridge before August 1. “If materials weren’t across by August 1, well, they weren’t going to get to the site,” said Grogg.

Again, this involved the logistics people making sure everything was delivered to the ports—if the components were coming from overseas—and to rail depots, so the August 1 deadline could be met.

“Everyone knew this was a number one priority, that there could be no delays, from the ocean travel of components, to moving them by rail, and then by truck.”

 
January/February 2011