The article is devoted to improving the methods of planning the development of an electric power system (hereinafter - EPS) for the long term. The list of tasks to be solved when planning the development of EPS, the formulation of the task of substantiating the development of EPS, and the features of its solution are considered. Within the framework of the study of the multicriteria formulation of the problem of substantiating the development of EPS, possible criteria for planning an EPS are proposed. Calculations were performed for two and four criteria. Based on the results obtained, conclusions were drawn about the prospects of a multicriteria approach to planning the development of EPS.