Improvement in plant performance with an increase in reactor steam dome pressure

The Perry nuclear power plant is a General Electric boiling water reactor (BWR-6) plant with a rated power of 3,579 MW(thermal). The plant operated at below-design reactor steam dome pressure during cycle 1 because the main steam line pressure drop was 0.138 MPa (20 psi) less than design. To adjust for this discrepancy in cycle 2, the turbine inlet pressure was raised from 6.65 to 6.79 MPa (950 to 970 psig) to increase the reactor pressure from 7.03 to 7.17 MPa (1,020 to 1,040 psia). The thermodynamic data collected before and after the pressure increase indicated both an increase in thermal cycle efficiency and an increase in fuel use. The thermal cycle efficiency increases electrical output an additional 1.4 MW(electric) at rated thermal power. The fuel use extends the fuel-power capability, before end-of-cycle (EOC) coastdown, by [approximately]2 days.