V84.2 turbines exceed guarantees
Thermal performance and emissions testing at Richard M. Flynn Power Plant, Manchester Street Station and Bergen Generating Station have confirmed the Siemens Model V84.2 gas turbines` ability to meet or exceed guaranteed performance levels. At the New York Power Authority`s (NYPA) Flynn plant, a 150 MW combined-cycle facility with one V84.2 unit, thermal performance testing was held in June 1994 following 6,200 actual hours of baseload, combined-cycle service.
The tests showed the unit`s heat rate was 2 percent better than its contract called for and its output on natural gas 1.5 percent higher than its guaranteed level. Air resource testing in November, 1995 demonstrated sustained NOx emissions held steady at 8.8 ppm or less for loads down to 50 percent of baseload while maintaining CO levels of 2 ppm or less under the same operating conditions. Testing on fuel oil showed NOx emissions below 42 ppm and CO of less than 5 ppm down to 50 percent baseload.
"Achieving 9 ppm NOx emissions dry allows us to optimize the Flynn plant`s life cycle costs by avoiding the high capital, operation and maintenance costs associated with selective catalytic reduction systems, as well as those associated with water and steam injection," said Michael D. Medvec, NYPA director of operations. The V84.2`s emissions performance is attributed to the multi-hybrid burner combustor. The Flynn facility had a 95 percent availability factor in its first year of operation. The gas turbine-generator demonstrated an availability factor of 96.5 percent, a reliability factor of 99.3 percent and a 100 percent starting reliability in 162 starts.
This 490-MW repowering project has been a showplace for New England Power Co. and Narragansett Electric Co. since its completion in 1995. Formal performance testing on the facility`s three 103-MW V84.2 units, conducted in the fall of 1995, revealed the units generating 2 to 3 percent more power and achieving a 2 to 4 percent better heat rate than guaranteed for natural gas and fuel oil. NOx emission levels fell into the 10 to 20 ppm range, below the 25 ppm level guaranteed by the manufacturer. CO emission levels were negligible, well below the levels mandated by the plant operating permits.
Part of a 650-MW repowering project, four V84.2 units at Public Service Electric and Gas` Bergen Generating Station, have demonstrated good operating results since commissioning in the fall of 1995. Thermal performance testing in October and November showed heat rates and power outputs better than the guaranteed levels. The units have demonstrated NOx emission levels in compliance with the guaranteed 9 ppm. CO and unburned hydrocarbon emissions were less than the 5 ppm guaranteed. Combined-cycle performance tests are to be conducted soon for the entire power plant operating on natural gas.
Manchester Street Station`s turbine hall. Shown here, the three V84.2 gas turbines installed as part of a repowering project in 1995.
Manchester Street Station, Providence, R.I.