Efficiencies of Thermal Plants During Transient Duty

Policies on economic operation of Power Plants commonly rely on incremental production costs which are based on steady state input/output plant characteristics. The Thermal Plant process actually involves considerable storage in metal and fluid which varies with load level and hence the input/output relationship during transient duty can be significantly different from that in the steady state. This paper described an investigation on the efficiency of Thermal Plants during transient duty. The specific objective was to determine the extent of irreversible thermodynamic losses due to load change duty. A detailed digital dynamic model of a prototype boiler-turbine and auxiliaries system was developed and used to assess transient efficiency effects. These investigations were sponsored by the Electric Power Research Institute.