Construction of wind energy transmission lines could begin in 2019 

RAWLINS – A project more than a decade in the making to build transmission lines supplying wind power generated in southern Wyoming to markets in southwestern states could see construction begin in 2019.

The TransWest Express Transmission Project looks to build power lines stretching from a terminal in Carbon County, just south of and in between Rawlins and Sinclair, to another terminal south of Las Vegas. The 730-mile transmission line with a 3,000-megawatt capacity would transmit power from the developing Chokecherry and Sierra Madre Wind Energy Project in Carbon County, where the first phase of construction began last year to install 500 of 1,000 planned turbines.

The Chokecherry and Sierra Madre wind farm is a project of Power Company of Wyoming. TransWest Express, a sister company of Power Company of Wyoming, is completing the steps to begin construction of the transmission line.

With up to 3,000 megawatts of power generation, the Chokecherry and Sierra Madre project would be the largest wind energy generation project in the United States, and is expected to have significant economic benefits for Carbon County and the rest of Wyoming. The transmission line is critical in making the most of the energy commodity, as it would allow markets in California, Nevada and Arizona to access it.

In the first year of construction, TransWest estimates it will pay between $3.4 million and $4.7 million in property taxes in Wyoming, and it would continue to pay property tax each year throughout the life of the project. It also estimates it will pay nearly $20 million in sales tax in Wyoming throughout the two- to three-year construction timeframe.

David Smith, TransWest director of engineering and operations, said the Chokecherry and Sierra Madre project is a $5 billion investment. The transmission lines are a $3 billion investment, with an expected $1 billion expenditure in Wyoming. He said the transmission line would be interconnected with the Chokecherry and Sierra Madre Project, as well as PacifiCorp’s Gateway West and Gateway South projects.

“Those lines will all be interconnected as part as the larger transmission system plan for the region,” he said.

Before construction can begin, however, TransWest has plenty of work to do. State and local permitting, private land acquisition, right-of-way access and surveying work is still to come, Smith said.

Additionally, he said coordinating the TransWest lines with existing and future energy transmission infrastructure has presented its own set of challenges.

“As we go and site the line, one of the main things was co-location with other transmission lines, pipelines and other things,” he said Wednesday during the Bureau of Land Management of Wyoming Industry and Government Conference in Rawlins. “We want to keep long, straight lines as long as we can, as well as minimize cost and impacts of the line.”

As the construction project begins, the transmission lines will be visible on the landscape south of Rawlins along the Interstate 80 corridor before cutting south just east of Wamsutter. It will go through northwest Colorado before crossing Utah on its way into Nevada. Two-thirds of the route crosses through federal lands, but Smith said TransWest is also negotiating with private property owners.

“There is some 500-600 landowners also that we’re now engaged with to get right of way for a 250-foot easement, as well as access to private roads,” he said. “We need construction and maintenance access to all the transmission lines throughout the operation. There’s not a lot of maintenance that goes on, but for liability reasons, we need to be able to get there.”

Most of the towers will have either three- or six-string conductors, Smith said. The structures are both steel lattice towers, one a guyed structure that he said would be most commonly seen on the lines. Each would be installed about 1,500 feet apart for the more than 700-mile distance, Smith said.

When complete, Smith said the life cycle of the project would span 50 or more years.