Sep. 28--With natural gas prices rising more than 30 percent this fall, the Tennessee Regulatory Authority urged consumers Tuesday to conserve energy to try to limit their winter heating costs.

TRA issued a consumer advisory to remind those heating their homes with natural gas about ways to limit their consumption to hold down rising gas bills. The authority issued its advisory after the state's biggest natural gas distributors entered purchased gas adjustments to boost their residential rates by some of the biggest amounts in three years.

Chattanooga Gas Co. said its natural gas costs are forcing a 29.8 percent increase in its commodity rates, effective Saturday.

"We try to buy and store some of our gas supplies in the summer when costs have usually been lower," said Steve Lindsey, vice president and general manager for Chattanooga Gas. "But this year, commodity prices have risen all year and hurricanes Katrina and Rita only made the market worse. There are obviously going to be some big impacts on prices this winter, so we encourage people to do what they can to limit any energy waste."

Although nearly 10 times the general rate of inflation, the increase by Chattanooga Gas this fall is still the smallest among Tennessee's major natural gas distributors. Nashville Gas is raising its rates by 40 percent and Atmos Gas is raising its rates by 42 percent, according to the TRA.

"Utilities are allowed to pass along the higher cost of the natural gas itself to their customers," said Darlene Standley, chief of the utilities division for the TRA. "The market sets those prices and they have definitely been higher this year."

Gas industry officials told the TRA this week that increased demand, insufficient supply and the Gulf Coast hurricanes have all combined to push the commodity price of natural gas up from last year's levels.

"Obviously, consumers cannot control the market and environmental forces that affect the availability of natural gas," TRA Chairman Ron Jones said. "However, consumers can certainly do their part in conserving energy and making sure their homes are prepare for colder months."

TRA has energy savings tips at www.state.tn.us/tra and Chattanooga Gas Co. offers energy savings ideas at www.chattanoogagas.com.