Avista electric rates will decrease 2.1 percent starting today, while natural gas rates will increase .3 percent.

For electric customers, residents using an average of 956 kilowatt hours a month will see a decrease of $1.79 per month for a revised average monthly bill of $82.02.

Natural gas customers using an average of 62 therms will see a 20-cent-per-month increase for a revised average monthly bill of $60.96.

The Idaho Public Utilities Commission granted Avista a base rate electric increase of 1.1 percent and a base rate gas increase of 1.6 percent.

However, in separate actions, the IPUC also approved annual electric and gas rate adjustments that pass through actual changes in expenses or credits and have no impact on company earnings.

Those adjustments offset all of the electric bill impact and part of the gas increase to customers.

"We are pleased the commission recognized the need for our rates to reflect the increased costs necessary to operate and maintain our energy system," said Dennis Vermillion, Avista Corp. senior vice president and president of Avista Utilities. "Making the effective dates for the multiple filings coincide for (today) means our customers will actually receive a decrease in their electric rates."

The settlement states that Avista agrees to not collect another base electric or gas rate increase before April 1, 2013. That does not include yearly tracker adjustments such as the power cost adjustment or purchased gas cost adjustment and energy efficiency rider adjustments.

In a prepared statement, the IPUC said the provision "provides an extended period of rate stability that otherwise might not occur."

Avista was granted 31 percent of its original electric rate increase request and 58 percent of its original gas increase request.

"We note that the stipulation and settlement represents a significant reduction in the requested revenue increase," an IPUC press release states.

The parties to the settlement are also directed to participate in workshops to address updating the cost of service to each customer class, rate design and low-income programs.

Avista serves more than 122,000 electric and more than 74,000 natural gas customers in Idaho.