4 Approximate computation of power generating system reliability indexes

Publisher Summary This chapter focuses on an examination of the computational aspects of two important power generation system reliability indexes, which are used in power system planning and production costing evaluation. The loss-of-load probability (LOLP) index for a power generating system measures the probability that system load exceeds its available capacity. Direct numerical computation of this index proves unfeasible, and one needs to resort to approximate methods. Approximation scheme proposed by Esscher is adapted in an actuarial context for evaluating the LOLP index. Numerical results given in this chapter demonstrate that this approximation is very accurate. A second problem considered is estimating the capacity factors of various units which experience different rates of utilization within the system. These indexes are used to determine the expected operating costs of an electric utility company. The computation of these indexes involves similar difficulties as that of LOLP. Also, for a typical system evaluated, Esscher's method provides very accurate results.