Electrical Engineering ⇒ Topic : Load Duration Curve

Load Duration Curve:- A load duration curve represents re-arrangements of all the load elements of chronological load curve in order of descending magnitude. This curve is derived from the chronological load curve.

Figure (a) shows a typical daily load curve for a power station. It may be observed that the maximum load on power station is 35 kW from 8 A.M. to 2 P.M. This is plotted in Fig. 18.3. Similarly other loads of the load curve are plotted in descending order in the same figure. This is called load duration, curve Figure (b).

                Figure (a) Typical daily load curve                                           Figure (b) Load duration curve

The following points are worth noting :-

• The area under the load duration, curve and the corresponding chronological load curve is equal and represents total energy delivered by the generating station.
• Load duration curve gives a clear analysis of generating power economically. Proper selection of base load power plants and peak load power plants becomes easier