Optimal short-term thermal unit commitment

Abstract

Fuel cost savings can be obtained by proper commitment of the available generating units. This paper describes a truncated dynamic programming method for the commitment of thermal units over a period of up to 48 hours. The commitment is such that the total cost is minimal. The total cost includes both the production cost and costs associated with the startup and shutdown of units. The startup cost for each unit is dependent on the amount of time the unit has been shutdown prior to startup. A variety of spinning reserve requirements are observed and crew constraints on the startup and/or shutdown of two or more units in the same plant are imposed on some of the plants. In addition, operation of individual units must satisfy the specified minimum up times and minimum shutdown times.