The Idaho Public Utilities Commission announced Friday afternoon that it had granted a significant one-year surcharge to customers of Idaho Power—the fourth larget adjustment on record.
The PUC said declining water flow, reduced revenue from surplus energy sales and ongoing wind power expenses were factors in the $140 million power cost adjustment.
As a result, Idaho Power residential customers will be assessed a one-year surcharge of an average 12.5 percent effective Saturday, June 1. For all customer classes combined, the average increase will be 15.3 percent.
For an average residential customer who uses 1,050 kilowatt-hours per month, the average monthly increase will be about $11.38.
The PUC cautioned that none of the money collected in the surcharge could be used to increase Idaho Power earnings or salaries. Instead, the PUC said the revenues would be "kept in a deferred account, audited by the commission, to be used only for paying extraordinary power supply expense."
Idaho Power said it had experienced a 19 percent reduction in water flow the company uses to power its hydroelectric plants.
The PUC said if it had spread the increase over two or three years, in order to soften the impact, it may have to add yet another surcharge on top of an existing surcharge in 2014 and 2015 if the state experiences even lower water levels.