Abstract: Integrated Resources Planning (IRP) and Demand Side Management (DSM) rooted in United States, the biggest country of electric power consumption. The appearance of the IRP indicates that humanity is entering into a new century of energy utilization. That is, under the requirements in material, civilization, and environment from human beings, the energy should be used economically and reasonably. The IRP has been listed in the key fields of humankind’s activity in twenty one century. Different from the conventional planning method, IRP is the process by which supply- and demand-side options are consistently planned, implemented, and evaluated to provide energy services at a cost that appropriately balances the interests of all stakeholders. Consequently, some energy saving measures may be adopted, such as, removing peak and filling vale. Therefore, it is not enough that only one electric load per year is predicted. It should be that an electric load curve per year is forecasted. Obviously, the latter is more difficult than the former.This paper discussed a combinatorial forecasting approach of electric load in IRP for electric power system. Partially, the approach has been applied in Daqing Oilfield successfully.

Key words: electric power system, integrated resources planning, demand-side management, forecasting