These turbines are part of a wind farm near Medicine Bow. The site was one of five
in Wyoming where data was gathered for the UW study. (Leann Naughton Photo)
Wyoming wind power could benefit the Colorado electric grid both economically and environmentally, according to a study headed by a University of Wyoming professor.
The report, titled “Wind Diversity Enhancement of Wyoming/Colorado Wind Energy Projects,” focuses on the importance of diversity in wind resources produced by Wyoming and Colorado, and the economic benefits the combination of these complementary wind sources could potentially provide, says Jonathan Naughton, a UW Department of Mechanical Engineering professor and director of the Wind Energy Research Center.
“I think many people had the idea that wind diversity would have an economic impact, but we had to put some numbers on it,” Naughton says. “I think that’s what this report did.”
Wind diversity essentially means wind speeds at two locations vary differently, Naughton says. Wind that blows at a high speed at one location while it blows at a low rate of speed at another, and vice versa, would be considered diverse sources of wind.
Making power created by wind less variable, or more consistent over time, would create a more even and reliable flow of power to communities using this energy source as well as improve the correlation of wind energy availability to the actual customer demand for electricity, Naughton says.
Plains winds in Colorado and the mountain-driven winds in Wyoming are largely uncorrelated due to the physical processes responsible for the winds at the different locations.
Wyoming’s wind blows harder than Colorado wind, and blows primarily during the day, which is the highest energy demand or peak period for Colorado energy consumers, according to the study. Wyoming wind can mitigate the ramping events associated with the variable renewable energy sources on the Colorado energy grid.
“The analysis shows that combining diverse renewable resources from Wyoming with those in Colorado would result in mitigating the amount of dispatchable generation required to address the variability of wind and solar,” Wyoming Infrastructure Authority (WIA) board member J.M. Shafer says in an April 2 WIA press release.
The report was commissioned by the WIA, which is based in Cheyenne. Created by the Wyoming Legislature in 2004, the WIA’s mission is to diversify and expand the state’s economy through improvements in Wyoming’s electric transmission infrastructure to facilitate the consumption of Wyoming energy in the form of wind, natural gas, coal and nuclear power, where applicable.
Naughton co-wrote the report with Thomas Parish, a UW Department of Atmospheric Science professor, and Jared Baker, a UW graduate student majoring in mechanical engineering. A U.S. Department of Energy grant funded a major portion of the study.
The study used one year of data, predicted by a weather forecasting model, for multiple sites in Wyoming and Colorado. Computer analyses were compiled from sites near Rawlins, Casper, Medicine Bow, the Southern Laramie Valley and the Wheatland/Chugwater region in southeastern Wyoming. Colorado sites included locations of existing wind farms at Cedar Creek, Peetz Table, Cedar Point, Kit Carson and Colorado Green.
A savings in the tens of millions of dollars annually would result from reduced payments for make-up power when Wyoming and Colorado resources are combined. Assuming the make-up power is derived from fossil fuels, reduction in greenhouse gases can be realized, Naughton says.
“It’s easier to integrate wind power into the grid,” he says. “It saves money you don’t have to use for backup power that would likely come from gas turbine engines fired by natural gas.”
For Wyoming’s wind resources to benefit Colorado, new transmission infrastructure would be required. According to the WIA press release, a transmission project -- the Wyoming-Colorado Intertie Project – that originates in Wyoming is in development. The 345 kilovolt AC line would originate in the Wheatland/Chugwater area and include an interconnection into the Colorado grid in Morgan County, which is located in northeast Colorado. That project, expected to be complete during 2017, is a public/private partnership between LS Power Group and the WIA.
A National Renewable Energy Laboratory (NREL) study, also commissioned by the WIA, was released the same day. The NREL study identified economic impacts relative to transmission and generation infrastructure across state lines.
During the three-year construction period, about 4,000 jobs -- 1,300 in Wyoming and 2,700 in Colorado -- would be generated annually. Annual wages would range from $52,000-$75,000 for the construction jobs. About 300 permanent jobs in Wyoming and another 100 in Colorado -- with wages between $41,000 and $63,000 -- would result, according to the study.
The UW wind study report was released to the WIA this week. It is the second in a series of four that compares the geographic diversity of Wyoming wind with wind resources in California, Colorado and Nebraska, and within Wyoming, Naughton says.
The report will be formally presented at the WIA’s spring board meeting at the Little America Hotel and Resort in Cheyenne May 15-16. The meeting is open to the public. For more information, visit http://wyia.org or contact holly.martinez@wyo.gov.
