In this paper, the supply function model is employed to simulate the bidding strategy of suppliers in the power pool, and models of the supply function with future contracts are presented. It is proved that only one of the parameters between slope and intercept of the bidding curve is an independent variable in order to achieve definite equilibrium. In the meantime, the equilibria of the bidding strategy about suppliers are studied when different intercepts of the bidding curve are chosen. Some examples are employed to study the Nash equilibrium strategies of suppliers with different future contracts in various bidding strategy models. The results show that the equilibria are different in different bidding strategy models, but the future contracts can effectively make spot prices decrease in all the models. (c) 2006 Elsevier Ltd. All rights reserved.