Puget Sound Energy has filed a request with the Washington Utilities and Transportation Commission (UTC) to pass through the higher costs the utility pays for purchasing natural gas supplies for its customers.

The Purchased Gas Adjustment (PGA) increase, which PSE has asked to take effect Oct. 1, would raise Puget Sound Energy natural gas bills by 11.1 percent overall, across all groups of customers.

For households using the year-round average of 68 therms of natural gas per month, bills would increase 10.3 percent, or $8.49 a month, on average. The rate change would bring the average monthly residential bill to $90.64 — about what the utility’s customers were paying in October of 2006. (The PGA request is separate from PSE’s General Rate Case currently in review with the UTC.)

Last season, for the 2007-08 winter, lower wholesale natural gas prices contributed to an overall 13 percent rate reduction for PSE customers.

“Natural gas prices have been very volatile and increased significantly since the UTC approved our request for a 13 percent reduction a year ago,” said Bert Valdman, PSE executive vice president and chief operating officer.

Puget Sound Energy offered homeowners advice on how to minimize high heating bills this winter and use energy wisely in their homes, including:

Avoid huge bills in the coldest months by paying a flat rate every month — balancing out winter’s high bills with summer’s low ones — through PSE’s Budget Payment Plan. Homeowners can call PSE at 1-888-225-5773 to sign up.

Seal up air leaks around windows and doors.

Have furnaces inspected and serviced to ensure proper working order.

Insulate attics, outside walls and floors over crawlspaces.

Find out if you qualify for PSE’s low-income bill-payment assistance plans, or for weatherization funding for your home. Contact PSE at 1-888-225-5773 to find out more about PSE’s HELP fund, The Salvation Army Warm Home Fund and Low Income Weatherization Program.

The PGA is a UTC-approved mechanism that allows Washington state’s natural gas utilities to periodically adjust rates to reflect changes in the price of natural gas charged by producers and wholesale marketers. The cost of natural gas purchased on the open market is recovered at PSE’s cost, without any profit to the company.

PSE also filed a separate request with state regulators to increase the monthly charge PSE customers pay into a fund for helping low-income households cover their utility bills. The monthly usage-based fee would increase by about 22 cents for electric customers and by 2 cents for natural gas customers. The fee provides approximately $15 million annually for a direct utility-bill assistance program to more than 25,100 customers served by PSE.