1998 Volume 118 Issue 4 Pages 428-436
Recently, the utility has been able to purchase the electric energy supplied from the Independent Power Producers (IPP) by a de-regulation in the electric industry. This paper evaluates the influence of IPP's uncertainty on utility and/or customer. In general, the production cost of energy supplied from IPPs is lower than that of a utility, however, the IPP's energy has more uncertainty compared with the utility's energy. This paper analyzes the effects caused by IPPs from the following three points: i) By modeling a process of determining purchased power price as a negotiation model, the authors evaluate the influence of its uncertainty on a potentiality to introduce IPPs through variation of the purchased price. ii) The authors evaluate a difference of power system reliability between a system under the de-regulated environment with IPPs and a conventional system without IPPs. It is assumed that the system reliability is determined by minimizing of the sum of supply cost and outage cost. iii) Finally, the authors evaluate that how the customer's various requirement about the reliability influences the introduced amount of IPPs.