Heat rate and maximum load capability improvements through cycle isolation
- Coronado Generating Station, Saint Johns, AZ (United States)
- Leak Detection Services, Inc., Annapolis, MD (United States)
Major improvements in maximum load capability and gross turbine heat rate were obtained at Salt River Project`s Coronado Unit 1, resulting from work done during the Spring 1993 overhaul. Corrected maximum load increased by 13.1 MW -- from 403.8 MW prior to the overhaul compared to 416.9 MW after the overhaul. Corrected gross turbine heat rate was reduced 270 BTU/kWH -- from 7,920 BTU/kWH before the overhaul to 7,650 BTU/kWH after the overhaul. Of the work done, the repair of leaking valves had the largest impact on cycle performance. The reduction of cycle leakage accounted for an increase of 9.9 MW in maximum load capability and a reduction to gross turbine heat rate of 190 BTU. Weekly maximum load tests, which started in August 1992 with the installation of an on-line monitoring system, show that maximum load had decreased approximately 4 MW during the six months prior to the overhaul. During this time there were no significant changes in HP or IP efficiencies, or any other directly-measured cycle parameters. Therefore, this degradation was attributed to cycle isolation valve leakage. Acoustic emission leak detection methods were used to identify leaking valves prior to the outage. Of the 138 valves tested for leakage, 31 valves had medium to very large leaks. Of these 31 leaking valves identified, 30 were repaired or replaced.
- Research Organization:
- Electric Power Research Inst. (EPRI), Palo Alto, CA (United States); Encor-America, Inc., Mountain View, CA (United States)
- OSTI ID:
- 114967
- Report Number(s):
- EPRI-TR-104241-V4; CONF-940540-VOL.4; TRN: 95:007224-0006
- Resource Relation:
- Conference: 1994 Electric Power Research Institute (EPRI) heat-rate improvement conference, Baltimore, MD (United States), 3-5 May 1994; Other Information: PBD: Jun 1995; Related Information: Is Part Of 1994 EPRI heat-rate improvement conference. Final report, Volume 4; PB: 400 p.
- Country of Publication:
- United States
- Language:
- English
Similar Records
Final Technical Report - Modernization of the Boulder Canyon Hydroelectric Project
Hanford Atomic Products Department. Monthly report, June 1966