<P> A load duration curve illustrates the variation of a certain load in a downward form such that the greatest load is plotted in the left and the smallest one in the right . On the time axis, the time duration for which each certain load continues during the day is given . </P> <P> There are some facts about the LDC that can be summarized as: </P> <Ol> <Li> the LDC is an arrangement of all load levels in a descending order of magnitude . </Li> <Li> the area under the LDC represents the energy demanded by the system (consumed). </Li> <Li> can be used in economic dispatching, system planning and reliability evaluation . </Li> <Li> it is more convenient to deal with than the load curve . </Li> </Ol> <Li> the LDC is an arrangement of all load levels in a descending order of magnitude . </Li>

Difference between load duration curves and load curves