History of Sterling's Municipal Power Plant Continued
With the decision to stay put at the current location, and with the removal of all steam equipment, a new wing was built to the west that would house a new unit, plus room for one additional future unit. A 1,000-hp Busch-Sulzer engine (pictured at left) was installed in the west addition in 1940.
In 1950, the 1928 De La Vergne unit was replaced with an inline 6-cylinder Nordberg (800-hp) in a new wing built to the north. An 8-cylinder Nordberg unit (1,600-hp) was also added to the plant capacity in 1955 to fill up the 1940 west wing expansion. In 1962, the 1931 De La Vergne unit was replaced with an inline 8-cylinder Nordberg (2,110-hp). These changes brought Sterling to an admirable compliment of generating efficiency. The modern Nordbergs would run on diesel and/or natural gas. In 1972, the 1940 Busch-Sulzer generator was replaced with a large V-12 Nordberg (3,700-hp). All four of these Nordberg units are still in use today.
In 1965, the City installed a sub-station for a supplemental outside power source with KP&L for use to offset loads that were gradually exceeding the limits of the plant’s capacity. In October of 1965, the City ceased being an “island” and purchased its first outside power. For the next 20 years, though, Sterling continued to generate most all of its own power around the clock.
During the early 1980’s, Sterling made a decision to discontinue 24-hour electric production and purchase the bulk of its power needs from outside sources. Low-cost, off-season baseload capacity was coming on-line around the state and region in the form of coal, nuclear, and federal hydro-dams. A small electric boiler was installed in the plant basement to maintain warm jacket water temperatures for the engines which facilitates rapid start and load capabilities in case of an unexpected outage. Sterling’s power plant would become a “peaking” plant and run only during seasonal periods of high power demand and prices on the regional grid. The plant continues in that capacity still today.
During the early and mid 1990s, Sterling’s increasing electric demand was approaching the capacity limit of the plant (6 Megawatts). The loss or breakage of any of the four units would have put the City in an undesirable position to purchase outside power during periods of high demand and prices. This began the consideration of updating our tie capacity, as well as adding additional units to cover the demand during the warm month “peaking” periods. In 1996, the plant sub-station (located directly west of the facility on the alley) was upgraded to increase the tie capacity and improve relaying equipment to eliminate “brownouts”, as well as replacement of the old-style switchgear in the building. In 2000, several Sterling representatives made a trip to Bisbee, AZ to look at three used Nordberg dual-fuel engine and generator sets that had been mothballed some years earlier. These three units would represent 4.5 Megawatts of additional capacity for the City. The purchase was made, and in 2001, the units and auxiliary equipment were dismantled and shipped to Sterling, overhauled, and set in a new expansion wing added to the south of the current facility. These 1,960-hp units all came on-line in May of 2002 and are still serving to add needed flexibility to our facility.
Over the years, Sterling has entered into several agreements with outside power sources to supply firm, low-cost baseload energy. We are currently near the end of a 10-year contract with the Grand River Dam Authority in Oklahoma (through the Kansas Municipal Energy Agency) to purchase 1.0 Megawatts/hour of energy half of each year during the cool months, and 1.5 Megawatts/hour of energy half of each year through the warm months for cost-based energy around the clock. We are already in the process of negotiating to renew or replace this energy to help keep purchased power costs down.
We are also nearing the end of a 20-year agreement in 2008 for off-season/off-peak energy with Midwest Energy (formerly a KP&L/Westar contract until the sale of our transmission area to MWE in 2004). We are already negotiating with several suppliers to replace this energy by June 1st, 2008.