As a result of increasing electricity demand in the last fifty years, there has been a rapid growth in power systems networks worldwide. Consequently, the power systems became more complicated for both routine load flow investigations and specialised analyses such as contingencies. A contingency can be either the addition or loss of a major transmission element or large generating unit. Therefore, more power buses with better interchange and online capabilities are needed to properly represent the networks with longer running time per study. In this book, the decoupled, fast decoupled, contingency, economic dispatch, probabilistic and stochastic load flow algorithms have been used to study a model power system such that the power systems operator can conveniently obtain up to date power flows and voltages subject to regulatory requirements for proper control; carry out operational planning for special events like sports, television programmes, maintenance, load shaving and load shedding activities, as well as long-term load planning, which are based on demographic and economic factors for correlating load uncertainties. Power Engineers, Economists and Planners stand to benefit