The Washington state Supreme Court will hear a challenge June 26 to state authorization of a major new wind power project planned in Kittitas County.

At issue is approval of Horizon Wind Energy LLC's Kittitas Valley project by Washington Gov. Chris Gregoire and the Washington Energy Facility Site Evaluation Council.

A local citizens group called Kittitas County and Residents Opposed to Kittitas Turbines challenged the siting council's and the governor's authority to pre-empt local land use regulations as well as other legal matters. A court decision is not expected until this fall, a siting council official said.

Horizon Wind is a subsidiary of Energias de Portugal. Under the state approval granted in September 2007, Horizon Wind will be able to build and operate turbines that will produce a total of 98 MW to 195 MW, depending on the output of the turbine models used.

Another Washington state wind energy facility, Puget Energy Inc. subsidiary Puget Sound Energy Inc.'s Wild Horse wind project, is set for an expansion of about 25 additional turbines. "They'll probably apply for that expansion this summer," said siting council Manager Allen Fiksdal.

Wind is not the only energy source expanding in Washington state. Fiksdal said that Invenergy LLC has informed the siting council that its 620-MW, natural gas-fired Grays Harbor unit entered commercial operation on April 25. Invenergy purchased the partially built gas plant from Duke Energy Corp. in 2005.