Historic Turbine Generator On Display

Historic Turbine Generator On Display Ottawa, Kan., is home to the first combination of steam and gas (STAG) turbines to drive a single generator with one fuel source. Based on jet engine technology, one turbine was powered by the burning fuel. The other was powered by steam created by the first turbine’s exhaust. The historic system has been recognized by the American Society of Mechanical Engineers (ASME). The STAG system was the first of many, and while no longer in use, it’s still in place, should it be needed. Post-World War II, General Electric (GE) let its jet aircraft engineers use the new technology to produce electricity. Early uses included gas turbine power to drive locomotives. However, the high-frequency noise made them less than popular, and the concept was abandoned after a few years. In addition to electricity generated by the gas turbine, exhaust heat was used to preheat water for a steam-powered generator. However, the steam was still produced by a separate boiler. Research led to new designs and improved efficiencies, and in 1967, GE introduced the first-ever pre-engineered combined cycle generator under the trade name STAG. The city of Ottawa commissioned the first STAG unit—an 11 MW Model 103. STAG quickly gained popularity, and within four years, GE faced competition from four major manufacturers producing similar power units. Within a decade, Ottawa’s leap of faith had grown into systems 50 times larger. The Ottawa unit had a gas turbine coupled to the forward end of the generator and a multi-stage steam turbine at the rear end. The gas turbine’s exhaust gas produced steam. The STAG 103 provided all the city’s power until 1979, when Ottawa began buying power off the grid. It relied on the STAG unit for backup power, along with two newer, smaller generators. When needed, it could be up to power in about 45 min. It was started in 2001 for inspection purposes. It was found to still be in good shape and fit for duty. Some maintenance was performed. Over the past 20 years, it has been started periodically for training and equipment preservation. STAG 103 was officially retired in place in 2020. Over its duty life, it logged 110,000 operating hours. ASME has recognized the system as a Mechanical Engineering Landmark. Such landmarks represent significant technological accomplishments. Visit the ASME Technology Library to learn more. Contact: FARM SHOW Followup, The American Society of Mechanical Engineers, Two Park Ave., New York, N.Y. 10016 (www.asme.org/about-asme/engineering-history/landmarks) or City of Ottawa, 101 S. Hickory, Ottawa, Kan. 66067 (ph 785-229-3600; info@ottawaks.gov; www.ottawaks.gov).

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