Deregulation and restructuring have become unavoidable trends to the power industry recently in order to increase its efficiency, to reduce operation costs, or to provide customers better services. The once centralized system planning and management must be remodeled to reflect the changes in the market environment. We have proposed and developed a multi-agent-based system to assist players, such as owners of power generation stations, owners of transmission lines, and groups of consumers, in the same market to select partners to form coalitions. The system provides users with a cooperation plan and its associated cost allocation plan for the users to support their decision-making process. Bilateral Shapley Value (BSV) was selected as the theoretical foundation to develop the system. The multi-agent system was developed by the combination of IDEAS [M. Klusch, Utilitarian coalition formation between autonomous agents for cooperative information gathering, in: S. Krin, G. O'hare (Eds.), Cooperative Knowledge Processing. Springer, London, 1996] and Tcl/Tk.