To view the application visit the Horse Heaven Application webpage

To view SEPA documents (like the EIS) visit the Horse Heaven SEPA page

Project background:

On February 8, 2021 EFSEC received an Application for a Site Certification (ASC) from Horse Heaven Wind Farm, LLC proposing the construction and operation of the Horse Heaven Wind Farm project. The ASC proposes the construction of a renewable energy generation facility that would have a nameplate energy generating capacity of up to 1,150 megawatts (MWs) for a combination of wind and solar facilities as well as battery energy storage systems (BESS). The proposed project is located in Benton County, Washington. According to the ASC, if approved, the Applicant is anticipating commercial operation of the first Phase to be built by the end of calendar year (CY) 2023.

The Applicant is seeking permitting authorization for up to 244 turbine locations and two solar arrays with their capacity dependent on the approved location, technology, and power market interest.

The Facility will utilize wind turbines and solar photovoltaic (PV) panels to convert energy from the wind and sun into electric power which is then delivered to the electric power grid. Two battery energy storage systems are proposed that would have a storage capacity of up to 300 MWac (megawatt capacity) using lithium-ion batteries.

Horse Heaven Pre-Operational Technical Advisory Group (PTAG)

The Site Certification Agreement (SCA) Article IV.G requires that the Horse Heaven Wind Power Project requires the Certificate Holder to establish a Pre-Operational Technical Advisory Group (PTAG) to advise on the development and implementation of pre-construction compliance activities. The PTAG is responsible for reviewing and providing technical advice on documents produced by the Certificate Holder related to wildlife and habitat, which will then be submitted to the Energy Facility Site Evaluation Council (EFSEC) for approval. After construction and before Project operation, the PTAG will cease to exist and be replaced by the Technical Advisory Committee (TAC).

The PTAG will be managed to provide timely recommendations as directed in the SCA, Article IV(G) and directed by the Facilitator, to support the Certificate Holder’s and EFSEC’s review. Appointees to the PTAG must have relevant expertise or firsthand knowledge of facts relevant and necessary to the matters on which the PTAG is established to advise. Documents related to the PTAG can be found below.

Horse Heaven Special Council Meeting

At the July 17, 2024 Council meeting, the Council deliberated on mitigation measures for the Horse Heaven Wind Project in consideration of the May 25, 2024 Governor response to the Council’s April 29, 2024 recommendation. Staff have prepared draft language, which is subject to Council consideration at the August 29, 2024 Special Council meeting.

Public comments were accepted from August 19, 2024 through August 25, 2024 11:59pm. 

August 29, 2024 Horse Heaven Special Meeting Recording

The Horse Heaven Special Council Meeting held a vote on Friday, September 13, 2024 at 3:30pm. 

September 13, 2024 Horse Heaven Special Meeting Recording

Comments Received

Comments received for the Horse Heaven Wind Project are categorized below and updated as soon as can become available.

Comments outside of a comment period can be sent to the EFSEC comment mailbox at any time: comments@efsec.wa.gov.

Important Note: Public comments submitted to the Council via the internet or in writing become public records under the Washington State Public Records Act (RCW 42.56). Information included in the comment such as the commenter's e-mail and mailing address becomes a public record once it is provided to EFSEC and may be subject to public inspection and copying if not protected by federal or state law. For additional information please see our Privacy Notice.

Draft EIS comments can be found on the Horse Heaven SEPA page

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