Big Horn I will contribute about 12% toward PSE’s remaining need to meet its 2030 clean energy targets. With a nameplate capacity of 199.5 MW, Big Horn I can generate enough energy to power about 70,000 homes annually.

“We are excited that this latest agreement with Avangrid helps us meet some of the most ambitious clean energy laws in the nation while delivering on our customer’s expectations,” said Craig Pospisil, Senior Vice President and Chief Development Officer at PSE. “We are proud to be a partner in developing Washington's wind resources—this project is another milestone in our continued investment in the state's energy economy."

Avangrid is upgrading components of the wind project to bring it to a like-new condition and extend its useful life. Avangrid will manage the construction with commercial operation expected by the fall of 2028.

“For more than two decades, Avangrid has been investing in Washington state to develop energy projects that support the region’s growing energy needs while delivering lasting economic benefits to the local community,” said Avangrid CEO Jose Antonio Miranda. “This agreement with Puget Sound Energy builds on our long history in this region and ensures Big Horn I continues to provide reliable electricity while sustaining local jobs, tax revenue, and long-term value for the region.”

Big Horn I achieved commercial operation in 2006 and is located in a larger renewable energy complex operated by Avangrid. Big Horn is sited on 14,297 acres, but the acres taken out of agricultural production is 1-2 percent, allowing the majority of the land for agriculture or ranching. The project received approval in August of 2025 from Klickitat County for the equipment upgrades under the existing conditional use permit.

Avangrid operates more than 11 GW of generation capacity in the country. PSE has successfully contracted with Avangrid before, specifically the Golden Hills, Lund Hill, and Klondike III projects, setting the stage for a reliable partnership.

Puget Sound Energy is actively building a cleaner energy portfolio to meet the ambitious requirements laid out in Washington's Clean Energy Transformation Act (CETA). Currently, about 58% of its electric portfolio is served by clean energy resources (up from 26% in 2019). PSE met the first major goal of CETA in December 2025 when it removed coal from its electric supply. Since 2019, PSE has added more than 3.3 GW of long-term renewable resources, with 1.1 GW already operating and the remainder coming online by 2027 and beyond.