The fate of one of Washington state’s largest proposed wind energy developments now rests with the state’s highest court, as opponents mount a legal challenge that could block hundreds of turbines from rising along a stretch of Interstate 82 south of the Tri-Cities.
Why It Matters
The Horse Heaven wind project would span roughly 72,500 acres and generate up to 1,150 megawatts of electricity — enough to rank among the most significant renewable energy installations in the Pacific Northwest. A court ruling against the project could reshape how Washington state pursues large-scale energy development, while a decision in its favor would clear the way for construction despite sustained opposition from local governments and tribal nations.
What Happened
The Washington Supreme Court heard arguments Thursday morning on separate petitions filed by Tri-Cities CARES, Benton County, and the Yakama Nation, each seeking to overturn the state’s approval of the project. The court agreed to take the case directly rather than route it through lower courts, after opponents initially filed suit in Thurston County Superior Court.
Scout Clean Energy, Inc., a Boulder, Colorado-based company, submitted its application for the project in 2021. The proposal calls for 244 wind turbines, each standing approximately 500 feet tall, along with three solar arrays on land stretching along I-82.
The project spent more than three years moving through environmental reviews and public comment before the Energy Facility Site Evaluation Council recommended approval in April 2024. The council initially scaled back the number of turbines as part of its conditions, but then-Gov. Jay Inslee pushed back, directing the council to focus on mitigation measures that would allow for close to full energy output. The council submitted a revised agreement in September 2024 that restored many of the turbine placement areas, and Inslee formally approved the project in October 2024.
The Legal Arguments
Opponents contend the approval process failed to comply with the state’s Administrative Procedures Act. The Yakama Nation raised a separate concern, arguing that the council did not adequately consult with the tribe before reaching its decision.
Scout Clean Energy pushed back on those claims. Its attorneys argued that the approval followed a legitimate and thorough process and that Washington needs the project. State Rep. Joe Fitzgibbon, a West Seattle Democrat who filed a brief in support of the project, argued that developments of this scale are essential to insulate the state from long-term climate-related consequences.
By the Numbers
- 72,500 acres — total footprint of the proposed project site
- 244 — number of wind turbines proposed
- 500 feet — approximate height of each turbine
- 1,150 megawatts — projected electricity generation capacity
- 3+ years — length of the environmental review and public hearing process
Zoom Out
The Horse Heaven case reflects a broader tension playing out across the Mountain West and Pacific Northwest, where large renewable energy projects are increasingly running into resistance from local communities, counties, and tribal governments who raise concerns about land use, visual impact, and the adequacy of consultation. That friction has complicated efforts by state governments to rapidly expand clean energy capacity.
At the federal level, the energy policy landscape has shifted considerably. The Trump administration has moved to support traditional energy sources, including a nearly $700 million commitment to the coal industry announced earlier this year — a contrast to the state-level push in Washington for large-scale wind and solar.
What’s Next
The Washington Supreme Court will deliberate following Thursday’s oral arguments, though no timeline for a ruling has been announced. A decision upholding the approval would allow Scout Clean Energy to proceed toward construction, while a ruling in favor of the petitioners could send the project back through the regulatory process or invalidate the approval entirely. All parties are expected to await the court’s written opinion before taking further action.
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