Sixty-nine turbines that PacifiCorp placed on the landscape between Laramie and Rawlins 20 years ago churn out the same amount of power that a mere dozen turbines could produce now.
That’s why they are coming down.
The utility has asked the local planning department in Carbon County for a permit to replace the wind turbines at Foote Creek Rim I with 12 new ones. That’s new nacelles, new towers and new blades. Where the existing towers reach about 200 feet from the ground, the majority of the new turbines will likely be closer to 500 feet tall, the length of a football field and then some, according to materials included in the local permit application.
Foote Creek was the utility’s first large wind project. Commissioned in 1998 and beginning power production the following year, the farm would be followed by many other wind projects in Wyoming.
The utility now owns and operates nine wind farms in the state and buys power from six additional wind facilities.
Currently, PacifiCorp is planning an expansion of its Wyoming wind fleet that will include three new wind farms totaling 1,150 megawatts of potential power. The farms will be located in the state’s band of profitable winds in Carbon, Albany and Converse counties.
The utility’s expansion will boost its wind capacity by 60 percent.
PacifiCorp is also repowering its nine existing wind farms including Seven Mile between Casper and Laramie and Rolling Hills north of Glenrock. The utility will replace wind blades with longer ones and install larger generators to harness more power from Wyoming winds. The towers and foundations at existing wind farms will be retained.
At Foote Creek, the repower is unique, said David Eskelsen, spokesman for Rocky Mountain Power — the western arm of PacifiCorp.
“Foote Creek I repowering is somewhat different from the repowering projects announced in the (Energy Vision) 2020 initiative,” he said. “Foote Creek is a complete replacement of the existing 68 foundations, towers, turbine nacelles and rotors (blades).”
Foote Creek’s existing turbines produce at best 600 kilowatts capacity each. The max production for the dozen replacement turbines ranges from 2 megawatts to 4.2 megawatts each. The total energy output from the wind farm, 41.4 megawatts, will remain the same. Overall capacity at the farm will increase marginally to 41.6 MW, according to an analysis filed with the county.
Over the 30-year estimated life of these turbines, Foote Creek is expected to generate $14.1 million more in tax revenue than it would with its current 69 turbines, according to a study provided to the county. That revenue is a combination of sales and use taxes during construction, increased income from Wyoming’s tax on wind energy and additional property taxes from the new structures.
As part of the repowering, PacifiCorp will become full owner and operator of Foote Creek. When built in the ‘90s, a water and electric board from Oregon was 21 percent owner of the Wyoming wind facility, and 37 percent of the projects power output was captured in a contract with Bonneville Power Administration.
The company will now acquire full ownership and the power will be available for use in the utility’s six state system.