New high temperature materials and improved blade cooling techniques have led 10 design of advanced models of industrial gas turbines with inlet or “firing” temperatures of 2350 degrees F. and higher. All major vendors now offer large new commercial gas turbine-generators, with outputs of 150 megawatts and higher, based on these new designs. These new turbine units offer higher overall performance and fuel efficiencies, with promise of better reliability and availability, as well as lower operating and maintenance costs.
EPRI began to assess the durability of early models of these advanced gas turbines (AGT) in 1991, by closely monitoring their performance during electric utility operation. The durability surveillance program, involving several AGT installations outlined below, will be described. However, only the first two sites involving GE units have produced a substantial operating history for discussion. The latter two sites have only recently had new AGT units installed by ABB and Siemens respectively. At the time of this writing, those new units are still being readied for utility operation. Their operating history under the durability surveillance program will be monitored, and discussed in a future paper.
• General Electric Gas Turbine Model MS7001F in peaking service at Potomac Electric Power Co. Station H at Dickerson, Maryland.
• General Electric Gas Turbine Model MS7001FA in baseload service at Florida Power & Light Co. Martin Plant at Indiantown, Florida.
• ASEA Brown Bovert Gas Turbine Model GT 24 initially in peaking service at Jersey Central Power & Light Co.(now GPU GenCo) Gilbert Station at Milford, New Jersey.
• Siemens Gas Turbine Model V84.3A in peaking service at Kansas City Power & Light Co. Hawthorn Station at Kansas City, Missouri.
The purpose is to determine the prospects for improved unit life cycle costs as a result of higher levels of performance, availability, reliability, and mantainability achieved by adding these engines to the industry fleet. This paper will describe the initial results from the Durability Surveillance studies, including observations from unit maintenance inspections as well as the output of advanced diagnostics and monitoring systems.