Timeline altered at 3GW site to dovetail with transmission

Construction of the sprawling 3GW Chokecherry and Sierra Madre (CCSM) wind project in Wyoming has been adjusted to align turbine installation with the availability of a $3bn transmission line so the power from the two-phase site has somewhere to go.

The Chokecherry and Sierra Madre wind energy project will be installed in Carbon Country, Wyoming (pic: J. Stephen Conn)

The project is still on track to qualify for the outgoing Production Tax Credit (PTC) and should be fully completed to ship power to southern California or neighbouring states by 2026.

Recent local news reports suggested the project had been delayed by five years, raising fears that it could suffer the same fate as AEP’s 2GW Wind Catcher project in Oklahoma.

Wind Catcher was cancelled a year ago after encountering permitting difficulties and regulators’ concerns about cost. But it seems CCSM will avoid this fate.

The developer of CCSM, Power Company of Wyoming (PCW), is also pursuing the TransWest Express (TWE) project, a $3 billion, 1,167km transmission line from Wyoming, across Colorado, Utah and Nevada to an interconnection point near Las Vegas.

Power from CCSM could be sold to Nevada, California or Arizona through the line, said a PCW spokeswoman.

TWE should be ready in time for the first 1.5GW phase of CCSM, to be completed in 2023-24, Roxane Perruso PCW’s vice president and general counsel, told the Industrial Siting Division of the Wyoming Department of Environmental Quality in a letter seeking the extension of the construction process.

Turbine installation at the second phase of CCSM will be completed by 2026.

Construction of both phases of CCSM, which started last year, consists of more than 132km of new roads and so far over 80 turbine pads.

In 2017, PCW had said that Phase I of CCSM would be complete by the end of 2020, with installation of the 500 turbines for the second 1.5GW phase in 2021-2023.

The wind farm’s new schedule is better aligned with demand for off-take in the southwest, said the spokeswoman.

Some 85% of the rights of way for TWE have so far been obtained, and construction should start in 2020, she said.

Wyoming has some of the best onshore wind resource in the US, but a population of fewer than 600,000.

The wind profile is also complementary to demand in California, unlike in-state solar power. Two recent California laws effectively mean the state is targeting 70% renewable energy by 2030.

"That’s a stretch, if not outright unachievable," said Anthony Logan, senior North American wind analyst at Wood Mackenzie Power & Renewables.

Regarding where an off-taker for the power is likely to be located, Logan said that the 100% clean energy targets that have been sweeping the region have been great diversifiers for CCSM, but nobody needs it "quite as urgently" as California.

Developing transmission in the US, especially across multiple states and a patchwork of private and public land — as is the case for TWE — is notoriously hard because of the myriad of permits needed and lack of standardised cost allocation.

The fact that PCW has achieved some 85% of the rights of way for TWE is astonishing, said Carl Zichella, director for Western transmission for NGO Natural Resources Defence Council.

"It’s as thoughtfully undertaken as any [transmission line] I’ve seen," Zichella noted.

It helps that PCW is owned by Colorado-based private conglomerate Anschutz, which has deep pockets — it owns oil and gas subsidiaries.

TWE is not the only transmission option for CCSM. Another would be to use PacifiCorp’s Gateway West and Gateway South transmission projects, which both go through the northern edge of the CCSM project site, added the PCW spokeswoman.

Gateway West started construction this year while Gateway South is to be completed in mid-2024.