Interruption costs, customer satisfaction and expectations for service reliability

This paper summarizes the results of a comprehensive study of the economic value of electric service carried out by Duke Power Company in cooperation with the Electric Power Research Institute in the US. In the study, customer interruption costs were estimated for generation, transmission and distribution outages of differing lengths occurring under varying circumstances. Interruption costs for momentary outages and voltage disturbances are also reported. In addition to these economic indicators of customer value of service, customer expectations for service reliability and power quality and their satisfaction with the service currently offered are reported. Statistical methods and procedures used in estimating interruption costs are described.