If you pay a Rocky Mountain Power bill in Cheyenne or Casper, nothing in this story will cut your monthly charge. That is worth saying up front, because most of the big clean-energy headlines out of Wyoming are not really about Wyoming's homes. They are about what leaves the state.
Wyoming already makes far more electricity than its residents use, and wind has become a genuine share of that output. The U.S. Energy Information Administration's state analysis credits wind with roughly 23% of Wyoming generation in 2024, up from about half as much in proportional terms back in 2019, and the raw output has more than doubled over the same stretch. Coal is still the largest source by a wide margin. But the direction on the ridgelines is clear.
The question that has dogged the state's wind country for twenty years is not whether the resource is there. Southeast Wyoming holds one of the densest concentrations of high-quality wind in the country, which is why a 320,000-acre ranch south of Rawlins became the site of the largest wind proposal in the United States. The question is the outlet: you cannot sell a megawatt you cannot move.
The outlet, not the fuel
The answer being built right now is called TransWest Express. It is a high-voltage direct-current line, roughly 732 miles from south of Rawlins toward the Desert Southwest, planned to carry on the order of 3,000 megawatts. Construction started in September 2023. Both the developer and the California ISO, which will receive much of the power, have described an in-service window around 2027. Dates on projects this large tend to move, so treat 2027 as a target rather than a promise.
Direct current is the point. The same physics that make long lines expensive to build make them efficient to run, and a line of this length is built to move bulk power from one end of the West to the other with limited losses. Wyoming becomes the sending end. The receiving end is mostly other states, whose utilities hold the contracts.
A project the size of a small city
At the Wyoming end sits the Chokecherry and Sierra Madre Wind Energy Project, developed by Power Company of Wyoming, an affiliate of the Anschutz Corporation. The company describes the project at roughly 3,000 to 3,550 megawatts, built in two phases on private and federal land, with the major federal and state permits secured and construction under way. The federal Bureau of Land Management issued the key rights-of-way between 2016 and 2020, which tells you how long this has been in the works.
For scale: 3,000 megawatts is on the order of three big coal units, or enough to serve well over a million households at average use, depending on the wind. The developer counts the permanent operations workforce at roughly 100-plus jobs once the turbines spin, alongside thousands of construction jobs spread across the build. The towers rise about 3 miles south of Rawlins and Sinclair, in a county where an energy payroll of any kind is worth noticing.
There is also a quieter revenue line. Wyoming levies a state wind production tax of $1 per megawatt-hour, and that money flows to county governments where the turbines stand. Add property taxes on the infrastructure itself and a wind farm becomes a line item in a county budget, not just a feature on a ridge line.
The honest math on your bill
So why will your bill not fall? Because Wyoming power is already cheap to make and your rate is set elsewhere. Most Wyoming homes are served by Rocky Mountain Power, whose rates are set through state regulation and whose costs span coal plants, transmission, and a multi-state balancing area in the Western Interconnect, where reliability coordination runs through the Western Electricity Coordinating Council. A new export line does not change the math of the plants and wires already serving your meter.
What changes locally is narrower and real: construction payrolls in Carbon County for years, a permanent operations staff, and tax revenue that shows up in county services rather than on your statement. If you live in Rawlins, that distinction matters. If you live in Gillette and heat with electricity, this story mostly passes you by, and honesty requires saying so.
The bigger strategic bet is on what exports buy the state: a second income stream from wind to sit beside coal and gas, at a time when the federal data shows coal's share of Wyoming generation trending down over the long run. Whether that bet pays out is a question this decade will answer.
Worth watching this fall
- TransWest Express construction progress reports. The developer posts segment updates; steady tower work through the winter is the sign the 2027 window is real.
- Phase milestones for Chokecherry and Sierra Madre. The project is built in stages, so watch for turbine delivery and first-phase energization notices rather than a single completion date.
- Rocky Mountain Power's Wyoming rate filings. This is the document that actually moves your bill, and it is updated on its own schedule, independent of any wind headline.
- Carbon County budget hearings. The wind tax and property tax revenue from the project area start showing up in county ledgers as phases come online. Routine, but it is where the money becomes visible.
Questions readers ask
What is the TransWest Express line?
A roughly 732-mile high-voltage direct-current transmission line from south of Rawlins toward the Desert Southwest. It is planned to carry on the order of 3,000 megawatts, and construction began in September 2023.
How big is the Chokecherry and Sierra Madre wind project?
The developer describes it at roughly 3,000 to 3,550 megawatts across two phases in Carbon County, with major permits secured and construction under way. Turbines rise about 3 miles south of Rawlins and Sinclair.
Will exported wind power lower my Wyoming power bill?
Probably not directly. Wyoming already generates more power than it uses, and your bill is set mostly by Rocky Mountain Power's costs and state regulation. The clearer local gains are construction jobs and tax revenue for host counties.
Who runs the grid in Wyoming?
Wyoming sits in the Western Interconnect, with reliability coordination across the footprint handled by the Western Electricity Coordinating Council, or WECC. Most Wyoming customers are served by Rocky Mountain Power.
When will the line and the wind project start operating?
The developer and the California ISO have both pointed at roughly 2027 for the line. The wind project comes online in phases rather than all at once. Dates this large tend to move, so treat both as targets.
Sources of record
-
U.S. Energy Information Administration, Wyoming state energy analysis
The federal government's official energy statistics. Source for the 2024 wind share of roughly 23% and the doubling of wind output since 2019. eia.gov/states/WY/analysis
-
Power Company of Wyoming, Chokecherry and Sierra Madre project pages
The developer's own figures for project size, phasing, permits, and jobs, on the order of 3,000 to 3,550 megawatts. We quote them as developer statements, not independent counts. powercompanyofwyoming.com
-
TransWest Express project site
The line developer's history of the route: roughly 732 miles, a planned 3,000-megawatt capacity for the direct-current segment, and the September 2023 construction start. transwestexpress.net
-
California ISO, transmission planning overview
The receiving-end grid operator confirms the TransWest Express scope, the 2023 start, and the around-2027 in-service expectation from the buyer's side of the line. caiso.com
-
Western Electricity Coordinating Council
The reliability coordinator for the Western Interconnect, the grid region Wyoming belongs to. Source for how the footprint is governed. wecc.org
-
Wyoming Energy Authority
The state agency's reference material on Wyoming wind resources and development, including the state production tax framework. energy.wyo.gov