Idaho regulators approve Avista power measure

SAN FRANCISCO, July 6 (Reuters) - The Idaho Public Utilities Commission said on Friday it approved a measure for utility Avista Corp. (AVA.N) to recover unusual power supply costs not included in base electric rates.

The annual adjustment will increase or decrease power rates for conditions outside the utility's control that can change supply costs, the commission said.

Conditions include changes in hydropower generation due to reduced river flows or unexpected changes in fuel costs or wholesale market prices for energy.

The cost adjustment measure is similar to one in place for Idaho Power Co. customers since 1993. Idaho Power is a unit of Idacorp (IDA.N).

Avista, which is based in Spokane, Washington, has about 115,000 customers in northern Idaho.

Customers will get a credit on their utility bill in years when power supply costs are less than what is already covered in base rates. They will pay a surcharge when power costs are higher than included in rates, the commission said.

A 2.45 percent surcharge to recover unusual power supply costs resulting from the 2000-2001 Western energy crisis was extended to Sept. 30. The new cost measure is effective Oct. 1.