Given the state of scientific research in the area of reliability of electric power systems (EPS) in the management of their development. Identified problems arising from the use of existed in the post-Soviet period, methodological developments in this area. Discusses the issues of changing conditions of receiving the initial information for solving problems assessment indicators of adequacy and capabilities with regard to UES of Russia. The comparison result of various representations of the initial information on the levels of redundancy combined EPS and UES Russia as a whole.

Key words: power system (EPS), indicators of adequacy, means reliability, generating capacity, power consumption, regulation, capacity reserve.