AST-41 Initiation Notice – Royal Slope Solar Project
Project Information
• Title: Royal Slope Solar Project
Project Location:
• Country: USA
• Street address 1:
• Street address 2:
• City:
• State: Washington
• Zip:
• County: Grant
Project Centroid Coordinates:
• Latitude: 46.909950
• Longitude: -119.903645
Project Sponsor Information
• Company Name: Royal Slope Solar LLC
• Project Sponsor: Clearway Energy Group LLC (Clearway)
• Street Address: 100 California Street, Suite 650
• City: San Francisco
• State: California
• Zip: 94111
• Name: John Woody
• Title: Authorized Signatory
• Work Phone: 415-734-0687
• Email Address: john.woody@clearwayenergy.com
Preferred Point of Contact
• Company Name: Royal Slope Solar LLC
• Project Sponsor: Clearway Energy Group LLC
• Street Address: 100 California Street, Suite 650
• City: San Francisco
• State: California
• Zip: 94111
• POC Name: Donette Miranda
• POC Title: Authorized Agent
• POC Work Phone: 503-880-5886
• POC Email Address: donette.miranda@clearwayenergy.com
Project Purpose
Please provide a concise overview of the purpose and objective of the proposed project.
The Royal Slope Solar Project (Project) includes a 260-megawatt (MW) utility-scale solar energy facility and accessory battery energy storage system (BESS, anticipated 260 MW, 4-hour duration), substation, transmission line, associated facilities, and a compensatory mitigation area located on approximately 3,231.8 acres of private land in unincorporated Grant County, Washington (Attachment A). The purpose of the Project is to provide a reliable, market-driven source of solar electricity to help meet growing regional energy demand and support state renewable energy and climate change goals. This Project will serve electricity users in Washington, with the target of serving Grant County specifically.
The transmission line connecting the solar facility to the existing Bonneville Power Administration (BPA) Vantage Substation would cross federal land managed by the U.S. Bureau of Reclamation (USBR).
The transmission line right-of-way on USBR-managed land requires a USBR license that is evaluated under the National Environmental Policy Act (NEPA), Section 106 of the National Historic Preservation Act (NHPA), and Section 7 of the Endangered Species Act (ESA). The NEPA public scoping process was completed in October 2022, initiating the Environmental Assessment (EA) development phase. In January 2023, USBR provided a schedule, which included conclusion of the NEPA process and issuance of the Decision Record in April 2024. Mainly due to delays as a result of the extended consultation process under the Section 106 process, USBR provided an updated schedule in February 2024, with the NEPA process concluding in September 2025. An updated schedule was provided in March 2025, with the Section 106 and NEPA process concluding in May 2027. Clearway supports robust Tribal engagement and is working collaboratively with USBR and affected Tribes to complete the process efficiently while maintaining cultural sensitivity.
The Project is otherwise ready to advance, with attainment of local permits. FAST-41 designation will help ensure transparent and timely coordination of the federal reviews critical to meeting Washington’s clean energy targets.
Project objectives include:
• Energy Contribution and Impact: The Project will address critical regional energy shortfalls and support economic development by generating 260 MW of energy—enough to power approximately 87,000 homes. The integrated BESS will enhance grid reliability by storing solar energy for use during peak demand or low generation periods.
• Siting Consideration: The Project is strategically sited on private land zoned as Rural Resources and Rural Remote, primarily consisting of lower-quality agricultural land. This site minimizes impacts on prime farmland, wildlife habitat, cultural resources, and nearby communities. The Project is also adjacent to existing infrastructure, including a transmission corridor and substation, and a Pacific Northwest marketing hub.
• Economic Benefits: Representing a capital investment of approximately $600 million, the Project will generate $3 million in annual local tax revenue, create over 325 construction jobs, and provide at least 11 full-time operational positions.
Project Description
Please provide a concise description, including the general location of the proposed project and a
summary of geospatial information, if available, illustrating the project area and the locations, if any, of
environmental, cultural, and historic resources.
The Royal Slope solar facility, BESS, and substation would be sited on private land in Grant County, Washington. The transmission line would cross USBR land.
The Project is located on parcels east of Washington State Route (SR) 243 and south of SR 26, approximately 1.5 miles southeast of the SR 243 and SR 26 junction in Grant County, Washington (Attachment A). A portion of SR 26 runs adjacent to the northeast portion of the proposed Project. The Columbia River is approximately 0.6 miles west of the Project. The Project will interconnect with BPA’s Vantage Substation located approximately 1.5 miles southwest of the Project solar arrays, and the town of Beverly is approximately 2.5 miles south of the Project boundary.
A full suite of environmental and technical studies have been completed including wetlands and waters, site characterization, raptor nests, Ute ladies’-tresses, habitat and wildlife, cultural resources, visual resources, phase I environmental site assessment, and a biological assessment. These reports support the development of the Grant County application and the NEPA EA and demonstrate readiness for construction.
Please see Attachment A for a map of Project location.
Technical and Financial Ability
Please provide a description regarding the technical and financial ability of the project sponsor to construct the proposed project.
Clearway Renew LLC owns 100% of Royal Slope Solar LLC. Royal Slope Solar LLC is technically and financially capable of completing the Project described in this application.
Clearway is one of the largest renewable energy companies in the United States, with nearly 6 GW in operation across 26 states and a nationwide pipeline of over 20 GW of assets.
Clearway has over a decade of experience developing, financing, owning, operating, and selling power from renewable energy projects—from clusters of small-scale community solar projects to some of the largest wind farms and solar plants across the United States. We have completed more than $11 billion in financings over the last few years to support the construction of more than 200+ projects. Clearway has proven expertise in delivering renewable power under long-term offtake contracts to corporations, governments, and investor-owned utilities to deliver clean, reliable, and cost-effective energy.
Clearway is a full-scope development and operations platform. We actively participate in every stage of the lifecycle of our projects from origination and development, through construction and financing, to commercial operations and long-term ownership. Clearway strives to create enduring relationships with our customers, counterparties, affiliates, and stakeholders.
The Clearway team offers a diverse range of experience, including longtime solar and wind industry leaders, energy engineers, project developers, investment specialists, and experts in environmental issues, permitting, interconnection, transmission, and power plant operations. The Clearway team is equipped and able to prioritize the success of the proposed Project and have extensive experience in their assigned specializations and roles on comparable projects.
Summary of Financing, Reviews and Authorizations
Please provide a description of any Federal financing, environmental reviews, and authorizations to be required to complete the proposed project.
The Project will require compliance with NEPA with USBR as the lead federal agency. The Project will also require permits from state and local agencies including but not limited to a Conditional Use Permit, State Environmental Policy Act (SEPA) determination, and Critical Areas review from Grant County.
The following table lists the primary discretionary federal, state, and local permits and approvals that may be required for the Project.
Federal Permits, Authorizations, or Inter-Agency Consultations
United States Department of the Interior, USBR
Land use authorization license under the Reclamation Act and Columbia Basin Project Act
NEPA EA and FONSI to support issuance of land use authorization license
USBR/Washington State Department of Archaeology and Historic Preservation (DAHP)
National Historic Preservation Act Section 106 Consultation
United States Department of the Interior, Fish and Wildlife Service
Endangered Species Act Section 7 Consultation
BPA
NEPA Categorical Exclusion
State of Washington Permits or Authorizations
Washington State Department of Ecology
National Pollutant Discharge Elimination System (NPDES) Construction Stormwater General Permit
State Environmental Policy Act Environmental Checklist Review and Determination
Local Permits or Authorizations
Grant County
Conditional Use Permit
Critical Areas Checklist and Assessment Review
Project Assessment
Assessment that the project meets the definition of a covered project as defined in 42 U.S.C. §4370m(6)(A) of the FAST Act and a statement of reasons supporting the assessment.
The Royal Slope Solar Project meets the criteria in 42 U.S.C. §4370m(6)(A) as a covered project as the Project represents a capital investment exceeding $600 million and requires federal
permitting under NEPA, NHPA, and ESA. Solar energy projects such as Royal Slope Solar, sited on USBR-managed public lands, are authorized as rights-of-way under Reclamation Act of 1902 and Columbia Basin Project Act, as amended and supplemented consistent with the Scattered Tracts Resource Management Plan. Environmental reviews for the Project will include an evaluation under NEPA as amended in 2023.
NHPA Section 106 consultation with USBR, DAHP, and Tribes is ongoing. Clearway has designed facilities and construction methods to avoid physical impacts on cultural resources, including proposing an approximately 5.5-mile-long alternative route to reduce visual and indirect cultural impacts.
In support of ESA Section 7, a biological assessment has been prepared finding no effect to listed species and formal consultation with the U.S. Fish and Wildlife Service is not anticipated.
FAST-41 designation will help facilitate interagency coordination and reduce delays that threaten the Project’s delivery of regional energy, economic, and reliability benefits.
Form Submitter Contact Information
• Name: Donette Miranda
• Title: Senior Environmental and Permitting Manager
• Work Phone: 503-880-5886
• Email Address: donette.miranda@clearwayenergy.com
Agreement
By submitting this application, I affirm that I am an authorized representative of the Sponsor indicated above and that the facts set forth in this form are true and complete.