A combination of higher summer rates and increased environmental-compliance costs will add about $19 to the average Westar Energy customer's bill this month compared to May, according to state officials.
Compared to June a year ago, the average customer's bill will be about $8 higher through the summer months, state figures show.
Westar, the Kansas Corporation Commission and the Citizens' Utility Ratepayer Board — who often disagree with one another — unanimously agree that conserving power this summer will likely be more important than ever before.
"This is not your old Westar rate. This one will hurt a lot more," said David Springe, consumer counsel for CURB, the state agency that represents residential and small-business customers.
"We just want to remind people to be cautious with their usage."
Westar spokeswoman Erin La Row said conserving is "very important for our customers, especially in light of the recession. A lot of our customers are struggling."
She said the number of customers on payment plans to make up past-due bills is up by 5,300 this year, with 35,000 on plans in May compared with 29,700 a year ago.
And without some changes in customers' behavior, things could get a lot worse in the coming months, officials said.
KCC and CURB analyses show that last month a homeowner using 1,641 kilowatt-hours of electricity would have paid about $141 in electricity and service charges.
That same amount of power now will cost $160.
The difference is even larger for larger or less energy-efficient homes.
A homeowner using 3,300 kwh — about the upper limit for a big house with two air conditioners — would pay $325 this month compared with $265 last month.
* Summer rates. In an effort to spur conservation, the KCC approved Westar charging higher rates during June, July and August, when electrical use peaks. The rates are structured in "rising blocks," so the cost per kilowatt-hour increases with increased use.
Winter or summer, Westar charges customers about 5.8 cents per kilowatt hour for the first 900 kwh a month. In winter, the cost per kilowatt-hour for use over 900 drops to about 4.6 cents. In summer, the cost of use over 900 rises to about 7.1 cents per kilowatt-hour.
* Environmental Cost Recovery. The KCC allows Westar to pass through to customers the cost of improvements it has to make to its plants to meet environmental standards. This year, that cost rose by about $13.8 million.
The KCC authorized higher summer rates to "send a message to use energy efficiently," said KCC executive director Susan Duffy.
The commission, CURB and Westar all hope that the higher rates will encourage people to reduce electricity use during the critical summer months.
Air-conditioning on hot summer days is by far the biggest driver of power use all year. The average customer uses about 600 kwh a month more of electricity in the summer than in the winter.
"That's huge," Duffy said.
The increased demand for summer power increases costs for all customers because when Westar can't meet the need with its base coal and nuclear plants, it has to turn on natural-gas-fired "peaking units" that are more expensive to run, La Row said.
In addition, lowering the demand for peak power in the summertime pushes back the day when Westar will need to build new power plants, which generates huge savings for customers, she said.
The environmental recovery charge has been included in Westar rates for about the past four years. It was instituted by the KCC to allow Westar to recover the money it has to spend to meet federally mandated environmental standards, primarily affecting its aging coal-fired power plants in the northern part of the state.
Last week, the commission issued an order allowing Westar to charge customers $46.2 million to recover the cost of 16 environmental improvement projects.
Last year's environmental surcharges totaled about $32.4 million, according to agency records.
The $13.8 million difference will add about 1 percent to customer bills, La Row said.