An Electric Power Purchase Strategy for Bilateral Contracts Focusing on Reliability of Customers

Abstract

With introducing the competitive electrical power market, large-scale customers can select electric power suppliers. Customers need to consider not only the economical efficiency but also reliability, to decide the amount of electrical power to purchase. This paper develops an economic electric power purchase strategy for customers focusing on reliability. A bilateral contract model expressing electric power suppliers as generators with a forced outage rate is proposed and introduced to assess potential outage risks of the bilateral contract between an electric power supplier and a customer. The outage-related cost, consisting of potential outage risks and the estimated outage cost, is also proposed and introduced as an index of the reliability on the customer side, and an optimal reliability level of a customer is obtained by using the index. Several numerical examples demonstrate the availability of the proposed electric power purchase decision method and reliability improvement strategies for customers are discussed.