From the standpoint of equipment needed and operating routine, the ideal load on a power plant
would be one of constant magnitude and steady duration. However, the shape of the actual load curve
(more frequently realized) departs far from this ideal, Fig. 3.7. The cost to produce one unit of electric
power in the former case would be from 1/2 to 3/4 of that for the latter case, when the load does not
remain constant or steady but varies with time. This is because of the lower first cost of the equipment
due to simplified control and the elimination of various auxiliaries and regulating devices.