This is an archived article that was published on sltrib.com in 2013, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

The intense secrecy surrounding the National Security Agency's new Bluffdale data center has sparked a lot of myths, including that the project will use so much energy it will strain Utah's power supply and drive up the electricity costs.

The facts, though, short circuit that rumor.

The U.S. Army Corps of Engineers has estimated the NSA facility will require 65 megawatts of electricity to run its equipment around the clock, which would put its annual power bill at about $18 million.

And while that is a lot of power — a single megawatt is enough to run appliances in 500 to 750 homes — it is nowhere near the amount of electricity gobbled up by Kennecott Utah Copper, for example, which uses approximately 200 megawatts to run its refinery, smelter and other operations.

In contrast, the Utah Data Center will use twice as much as Hill Air Force Base, which typically requires nearly 30 megawatts to power its operations.

The NSA center "won't be our largest industrial customer," Rocky Mountain Power spokesman Dave Eskelsen said.

Utah's largest electric utility has known for several years the Utah Data Center would need a lot of energy to power its huge banks of computers. That gave Rocky Mountain Power ample time to ensure it had the resources to meet that additional demand on its system.

Eskelsen noted that next summer the utility will bring online a second generating unit at its natural-gas-fired Lake Side power plant on the eastern shore of Utah Lake. That unit will produce an additional 645 megawatts of electricity, or nearly 10 times what the NSA center will draw from the area's power grid.

Rocky Mountain Power's large industrial customers pay less for each kilowatt of electricity they use than its residential customers, although those big power users make up for the difference in the volume they buy.

The Utah Data Center, for example, will use up to 65,000 kilowatts of electricity — 1 megawatt is the equivalent of 1,000 kilowatts — and will pay between 2.7 cents to 4.3 cents per kilowatt hour depending on the season. Typical Rocky Mountain Power residential customers pay about 9.8 cents per kilowatt hour depending on the amount of power used and the time of day they use it.

Large industrial customers get a price break because the demand they place on the utility's generating and distribution resources typically doesn't ebb and flow throughout the day like that of residential consumers, who use more electricity in the evening or on extremely hot days.

That means Rocky Mountain Power must invest more capital to ensure it can provide residential customers with electricity during peak demand times than it does its industrial customers.

Even though consumers pay more for the electricity they use, that doesn't mean they are subsidizing industrial customers, or vice versa, said Gary Widerburg, a Utah Public Service Commission spokesman.

"Rates are designed to ensure that each group pays its own way," he said.

In the NSA's case, that also meant the federal government had to build its own substation to serve the data center. Substations, which can cost $1 million or more to build, take electricity from transmission lines and transform it from high to lower voltage. They also are equipped with circuit breakers to ensure that power can be cut off in the event of an emergency.

"When it comes right down to it, the NSA facility in terms of the electricity they use won't be any different than the eBay data center or any other data center we serve," Eskelsen said.