PAYSON — It all depends on what your definition of tall is.

It looked for a time as if Payson's new power plant would hijack the title of Tallest Structure in Utah County.

Now, it's more likely that the building's smokestack will come close, but Brigham Young University's Kimball tower will retain its crown as Utah Valley's tallest building.

When completed in June 2004, the Payson smokestack will rise 150 feet into the air, said Ron Crump, Payson Power superintendent. However, the building itself will be 75 feet tall, while the Kimball Tower measures 161 feet, 6 inches.

And as smokestacks go, Provo city's still outdo everybody at 230 and 240 feet.

The high-profile Payson plant, located on the west side of I-15, will generate power for 17 of the 45 cities joined together under the umbrella of the Utah Associated Municipal Power Systems. The cities issued bonds to pay the $100 million construction bill, and power sales will pay off the bonds, Crump said.

The clean, natural gas-fired plant will kick out 140 megawatts of juice to Utah Power transmission lines, far more than the other power plants in Utah County in Payson, Springville and Provo. Payson's existing plant generates a mere nine megawatts.

The power plant is insurance for cities previously subject to the mercy of open market pricing. The member cities will now have a cushion should prices skyrocket like they did after the 2001 Enron scandal. That event created shock waves that sent Payson power rates as high as the city's new smokestacks. The fluctuations prompted Springville's city council to adopt a power-rate adjustment measure that is still in force today. The adjustment passes extra costs on to ratepayers, city officials say.

Stabilizing power rates was a chief reason the association launched plans to build its own plant after Crump invited the consortium to come to Payson. While natural gas prices still directly affect rates and remain high and volatile, officials hope the new plant will give member cities the same kind of price stability Provo enjoyed though its ownership of its own generating plant.

Fuel is readily available from a new natural gas line built by Questar. Steam supplements the gas-fired engines, making Payson's the first combined-cycle, gas- and steam-fired power plant in Utah, said Jackie Makin Coombs, customer service manager for the association.

Natural gas will initially drive the turbine, while steam from the turbine's exhaust will be recaptured and recycled to reduce air pollution. A total of 67 megawatts of power will be gas-generated at 98 degrees Fahrenheit. The steam generator will produce the remaining power to reach 140 megawatts.

All the power has been pre-sold, with most of it designated for Payson, Springville, Lehi, Logan, Kaysville, St. George and Page, Ariz.

The plant will also serve Ephraim, Fairview, Fillmore, Herriman, Hyrum, Santa Clara, Spring City, Springville and Washington.

Strawberry Electric Service, which serves southern Utah County, also joined the group.