Kennecott's Central Power Station
This page last updated on May 1, 2019.
In 1906, a steam electric generating plant was begun below the Magna complex. As power requirements increased, Utah Power & Light Company supplied electricity to meet demands. Additional transforming stations were added above the mill, and a power plant was added in 1918. (Phillip Notraiani, Utah History Encyclopedia)
The original steam plant at Magna generated 8.5 megawatts and supplied electric power to the Magna mill and the Bingham mine. (Mining Congress Journal, May 1940, Volume 26, Number 5, page 12)
The merger with Boston Consolidated in 1910, as well as an overall increase in production, "required much more power than could be economically generated by the original power plant; consequently, this plant was abandoned in favor of purchased hydro-electric power." (Mining Congress Journal, May 1940, Volume 26, Number 5, page 12)
Utah Copper Company announced that it would convert its mills and Bingham mine from steam power to electric power, purchasing the electric power from Telluride Power Company. "This will result in closing down the immense Magna power plant of the company, though the equipment will be kept intact to be called into service in case any emergency may arise." (Salt Lake Telegram, September 13, 1912; Salt Lake Herald, September 14, 1912)
In September 1927 all electric power used at Bingham was coming from Utah Power & Light Company. (The Mining Congress Journal, September 1927)
March 24, 1944
Central Power Station at Magna went into service at a cost of $8 Million. The boilers could use either natural gas or coal. (Kennecott Historical Index)
The Central Power Station at Magna went into service. Construction had started in February 1942. Prior to building its own power station, Utah Copper had purchased all of its electrical power from Utah Power & Light. (Park Record, November 2, 1944)
Central Power Station was expanded to 110 megawatts. (Arrington: Richest Hole, p. 75)
Foundations were laid for two new 25 megawatt generators, and a new boiler, at the Central Power Station in Magna. The original plans for the power station had included these generators when the plant was started in 1942, but wartime shortages forced design to be cut back. The expansion was reported as costing $3 million. (Garfield County News, August 14, 1947)
Kennecott Copper awarded a contract for the construction of a new 75 megawatt power plant to Rust Engineering, Inc. of Pittsburgh, Pennsylvania. It was reported that when completed, the new power plant would boost the total capacity of the central power station to 175 megawatts. (Mining Congress Journal, June 1958, Volume 44, Number 6, page 106)
December 19, 1958
"Construction work was started this year on the second major project to increase the operating efficiency of the company. Most of the foundation work and other initial installations have been completed on the $16,000,000 expansion project at the Central Power Station. The project includes the installation of a 75,000 kilowatt turbine generator, new boiler, cooling towers, electrical switch equipment, a 20-foot extension to the present building and other related work. When completed, it will boost the total output of the power plant from its present 100,000 kilowatt capacity to 175,000 kilowatts. The plant supplies all the power for the mine, mills, refinery and electric railroad." (Bingham Bulletin, December 19, 1958)
Central Power Station was expanded from 100 megawatts to 175 megawatts, to furnish power to the smelter. (Kennecott Historical Index)
Kennecott's new 75 megawatt generator was being tested during June 1960; full operation was to begin "within the next few weeks." The overall cost was reported as being $16 million. Planning started in 1957 and construction began in March 1958. The power station used natural gas, with coal as a standby. (Deseret News, June 1, 1960)
Kennecott closed its 175 megawatt coal-fired generating station because of financial losses. In the meantime, Kennecott could purchase power from Utah Power and Light at a reduced rate. The generating station's 100 employees remained working for maintenance purposes. (Coal Age, Volume, number 6, June 1983, p. 33, "Coal in Brief, Plant Closed")
In December 2010, Rio Tinto proposed to replace three coal-fired boilers at its Magna power plant, with a single natural gas-fired turbine and generator. The largest coal-fired boiler (Unit 4) will remain in use to give the power plant an alternate source of fuel. Unit number 4 was completed in 1959 and has always had the capability to be fired by either natural gas, or by coal. The improved power plant is needed to provide additional power to the planned Cornerstone project at the Bingham mine.
As of 2010, there were four units at the Central Power Station, with the following capacity:
- Unit 1, completed in 1944, 50 megawatts
- Unit 2, completed in 1947, 25 megawatts
- Unit 3, completed in 1947, 25 megawatts
- Unit 4, completed in 1960, 75 megawatts
The new natural gas-fired turbine will generate 175 megawatts of power, matching the current output of all four units of the current power plant. Unit 4, with its current capacity of 75 megawatts, fired by either coal or natural gas, will remain in service.
The exhaust from the turbine will be hotter than the current boilers, allowing its waste energy to be captured and used to produce additional steam that will in-turn be passed to the generators currently used by Units 1, 2, and 3, generating an additional 100 megawatts of power. The upgrade project will give the power plant a total capacity of 350 megawatts, doubling its current capacity.
"Kennecott's existing power plant does not operate during four winter months to help reduce air pollution in the Salt Lake Valley during inversions, but it is permitted to operate year-round on natural gas. Historically, it has been more cost-effective to buy power from the grid during winter months. The new natural gas plant will also be permitted to operate year-round with the ability to produce up to 275 megawatts (MW) of electrical power, up from 175MW today. The existing Unit 4 will continue producing up to 75MW of power using coal or natural gas." (https://www.oquirrhtimes.com/; obsolete web site, broken link)
October 27, 2016
"The Utah Public Service Commission today approved a multi-year contract between Rio Tinto Kennecott and Rocky Mountain Power to provide savings and stability for the mining company and energy provider’s customers. As part of the agreement, Rio Tinto Kennecott will shut down three of its coal burning power units more than one year ahead of schedule after negotiating a contract to continue receiving electricity from Rocky Mountain Power." (Rocky Mountain Power press release, October 27, 2016)
The following is compiled from multiple sources, all in the late October 2016 time frame:
-- A new agreement between Rio Tinto Kennecott and Rocky Mountain Power means three coal-burning units in the Salt Lake Valley will close a year earlier than expected.
-- A nine-year power-purchasing deal between the two companies and approved by the state this week will allow three of four power-generating, coal-burning units in Magna to be shut off permanently.
-- The closure of the units will eliminate an annual 3,500 tons of emissions along the Wasatch front.
-- State regulations didn't permit those units to burn in winter months. The three units have already been shut down for the winter and will not be fired back up in the spring.
-- Officials with Rio Tinto Kennecott say there are no “foreseeable” plans to shut off the Magna operation’s fourth coal-burning unit.
May 1, 2019
Rio Tinto Kennecott agreed to buy 1.5 mW of electric power from Rocky Mountain Power, certified as renewable energy sourced from Rocky Mountain Power's facilities in Utah and wind power facilities in Wyoming. (Rio Tinto press release dated May 1, 2019)