ABSTRACT
The first applications of on-line computers in power systems originated in the need for a central facility to economically operate several generating plants supplying the load of the system. Power systems often have a mixture of generating plants, including coal-fired steam turbine generators, oil or natural gas combustion units used for peak periods, hydro installations, pumped storage units, solar conversion, and nuclear generation. Regardless of the unit’s operating mode, it has a contribution to the economic operation, even though its output is changed for different reasons. Economic operation is defined in terms of fuel cost per power generated even though the true cost could involve capital investment and maintenance, depreciation, and so on. The discontinuities in the operating cost curve may be due to the firing of additional boilers, steam condensors, or other discrete equipment necessary to extend the power output of the generator from minimum to maximum.
