Your power bill could go up next year, but Idaho Power says customers will benefit

Residential customers of Idaho Power could see an increase in their monthly power bills next year if the utility is allowed to close down its North Valmy coal-fired power plant earlier than planned, a move Idaho Power says will benefit its customers.

Idaho Power last month asked the Idaho Public Utilities Commission to compress depreciation on the two-unit Battle Mountain, Nev., plant to shut it down by 2025. Planned retirement for one unit was 2031; the other was set to shut down in 2035.

If approved, that would increase the utility's base rates by $28.5 million — about 2.5 percent. The company says retiring the plant early saves customers about $103 million in today's dollars in the long run.

In addition, Idaho Power has asked for a 0.6 percent increase to base rates to update depreciation on its remaining plant assets. The combined 3.1 percent base rate increase would mean a bump of about $3.08 per month for the average residential user.

The PUC is allowing parties to intervene in either request until Dec. 5. If the proposals are accepted, rate increases would go into effect on June 1, 2017.

Idaho Power said a decrease in electricity market prices has made operation of the Valmy plant uneconomical except to meet peak energy needs in extreme temperatures.

Nicole Blanchard: 208-377-6410, @NMBlanchard