Newest IP plant turbine goes online

The new 170-MW gas-fired turbine at Idaho Power's Evander Andrews power plant near Mountain Home officially went on line last week, prepared to provide power for periods of peak demand this summer.

The project came in ahead of time and under budget, Idaho Power officials said. Including transmission lines associated with the project, the overall cost of the expansion of the plant was just under $80 million.

This week, Idaho Power hopes the Idaho Public Utilities Commission will approve a rate hike to pay for those costs, which will amount to just over $1 a month for most residential customers.

The plant can provide power to more than 110,000 homes.

The new turbine, essentially a huge natural gas-fired jet engine, is the third to go on-line at Evander Andrews, but nearly doubles the output of the two other turbines already there. Both the Evander Andrews plant, and the Bennett Hills plant just above The Pilot, are designed to provide power that exceeds the baseline demands of Idaho Power customers, especially during the hot summer months in July and August, and the cold months in the middle of winter.

"This is a celebration of our newest resource," Idaho Power's senior vice president for power supply, Jim Miller, told reporters attending a special open house for the new turbine last Thursday.

It's also, he noted, an example of how Idaho Power is attempting to upgrade it's facilities to the latest -- and greenest -- technologies.

In the past, Idaho Power often sold excess power to other utilities in the western power grid. Today, as the population of Idaho has grown, it is occasionally forced to buy power from other resources, especially during periods when demand peaks above its baseline needs.

Idaho Power relies at present primarily on hydro-electric sources for its energy needs -- one of the reasons it is able to provide some of the cheapest power in the nation to customers. But no new dams can be built on the region's major waterways, and as each of its older dams comes up for license renewals (Swan Falls is next on the list), environmental constraints have actually reduced some of the output of those dams. Combined with higher demand due to both population growth and the huge increase in the number of extra appliances found in homes today (such as TVs, stereos, and computers, in addition to stoves, refrigerators and washing machines), Idaho Power is now having to look at other sources of power generation.

In previous long-range projections for power the company had anticipated using coal-fired plants to generate the extra power it needed. But the cost of coal and the need to ship it to plants has risen dramatically, and increased environmental awareness has made coal-fired plants considerably less attractive.

"Right now, we're looking at a number of alternatives," for the company's long-range power needs, Miller said, including geothermal resources and wind-powered electrical generation. Most of those resources will probably be accessed by contract with private developers, such as the two windfarms in Elmore County expected to go on-line sometime during the next year (making this county one of the top producers in Idaho for wind-generated power).

But despite increases in costs for natural gas (usually a byproduct of oil production, and therefore tied to the increase in oil costs), gas-fired turbines are currently high on the list of Idaho Power's immediate plans for additional power generation.

Idaho Power currently is accepting a request for proposal for a private company to either build and operate, or build and sell to IP, a huge 250-600MW gas-fire plant that would be added to the company's base-line power generation system.

Whereas Evander Andrews and Bennett Hills are fired up only when needed, the proposed plant, which the company hopes to have on-line by 2012, would run full-time.

Elmore County is being considered as one of the locations for the proposed plant, although for purposes of air quality permitting it would almost certainly be a separate facility from the Evander Andrews and Bennett Hills facilities. Plants such as those that use liquid propane (LP) produce small amounts of nitrous oxide and carbon dioxide as byproducts and it is easier to obtain an air quality permit for a new site than it is to expand an existing site.

To build such a facility, Idaho Power has two basic criteria -- that it be located near areas where demand for power is high, such as the Treasure Valley with its large and growing population, thereby keeping power losses through transmission lines low, and that it have access to a natural gas source. A large LP pipeline runs through Elmore County.

Due to air quality permitting requirements, the company has ruled out locating the plant in Ada or Canyon counties, which are nearly at the limit of allowed CO2 emissions from existing businesses and industries there.

"If we were to locate in Ada or Canyon counties," Miller said, "it would pretty much max out the air shed and that would put a serious crimp in the economic growth there. We don't want to bring economic growth to a halt because of our plant."

That leaves either Elmore County to the east of Boise/Nampa/Caldwell or counties along the LP pipeline to the west as the most likely sites for a major gas-fired plant.

In addition, Miller said Idaho Power was considering -- long range -- the use of nuclear power to add to its energy generating capacity. While the company has had contact with the developers of a proposed nuclear power plant in Elmore County (and even has given them some advice), Miller said that plant is in such a preliminary stage of its proposal that serious negotiations to purchase power from it have not begun. The company is, however, looking a little more seriously at a proposal for a power-generating next-generation reactor that could be built on the Idaho National Laboratory reservation between Arco and Idaho Falls, the home of several experimental reactors, but that proposed plant would not be available, at the earliest, until early in the 2020s.