Congestion management and pricing in the restructured power system of Lebanon

Within the framework of a pool model to restructure the Electricite du Liban (EDL), this paper proposes a methodology to solve the transmission congestion and tariff setting problems that may arise in a privatized or partially regulated power utility. The limits of a secure system dispatch are first identified through solving a minimum load curtailment (MLC) problem. An optimal power flow problem, within the bounds of security defined by the MLC problem, is then solved to minimize the generation costs subject to satisfying energy demand, the network flow constraints, and generators´ capacities. The incremental nodal costs of electricity are then deduced from the dual variable of this OPF problem. A method for allocating fixed generation and transmission costs across the nodes is also presented. The present problems of the EDL system are briefly discussed and simulation results of the system working in the restructured environment are presented. The effects of strategic bidding by generators, and the use of MLC sensitivities to deduce operational and investment indicators are presented and discussed.