Resumen del autor, extraído del trabajo. In petrochemical plants, energy is used in the form of steam and electrical power. Electrical power is provided from an external source and part of it is produced at the plant site from turbine generators. Steam is produced in boilers, generated in processes, or recovered from heat exchangers. Steam is a working fluid for turbines, a heat transfer media and sometimes injected directly into a process. Energy requirements of the process units are not constant. Demands for energy also change as individual unit production rates change. Energy efficiencies of boilers change with loading and those of turbines likewise are a function of throughput. The cost of fuels burned in each boiler varies with the type of fuel and rate of consumption and the cost of power purchased from the electrical power company is a complex function of base consumption level, actual power consumption, peak demand, time of day and day of year. To minimize the net cost of providing energy to the plant, the operations of the energy management system should be optimized. Although many efforts have been devoted to the study of synthesis of heat integration and utility systems, but they are not flexible to demand changes. As plant demands change, operating conditions that minimize energy costs also change, often requiring re-optimization many times a day. Therefore, for the optimization system to be successful, modeling and computational simulations for the energy distribution system are the essential pre-requisite. The objective of the present work is to develop a model for energy distribution system to optimize the operations of the plant-wide energy management system. The results are in agreement with plant operational data.