The effects of uncertainties in forced outage rates and load forecast on the loss-of-load probability (LOLP)

This paper presents an analysis of how the loss of load probability is affected by uncertainties in the estimated forced outage rates of generating units and the forecast peak loads. Equations were derived for calculating the mean and the variance of the LOLP distribution under these uncertainties. Results for a sample system computed by the proposed method and by simulation show good agreement. The LOLP distributions obtained by simulation show that they can be approximated by the gamma distribution in the general case, and also by the normal distribution when only load forecast uncertainty is considered. It is demonstrated that consideration of load forecast uncertainty increases both the mean and the variance of the LOLP distribution.