The design of the energy management is a basic problem in the preliminary design of complex buildings. The structure of the energy management is a set of main energy equipment, as well as relationships between them. For modern complex buildings the set of possible variants of the structure of energy management is numerous. The aim of preliminary design is the choice of the optimal variant of the energy management structure. The paper deals with the selection of the energy management structure of complex buildings. In order to achieve it, the algorithm of elaboration of the set of variants and the determination of the structure of the "input-output" matrix has been developed. The paper contains the example of the determination of the binary "input-output" matrix for an office building. For the selected variant of energy management the energy balance sheet has been completed. (C) 2009 Elsevier Ltd. All rights reserved.