Outage cost of industrial customers in distribution and subtransmission systems for reliability improvement

This paper presents calculation methods of industrial customer outage costs in 22-kV and 115-kV power systems. In this study, the 302 industrial customers in the central region of Thailand are on-site interviewed for the outage cost study. Subsequently, the customer damage functions are derived from survey data via on-site interviews in 2006-2007 and mail surveys in 2008. These customer damage functions contain two parameters that represent outage cost per momentary interruption and outage cost per duration. The customer outage costs of both of 22-kV and 115-kV power systems are assessed and compared with revenue losses due to power outages of electric utilities. The results could be applied to prioritize distribution and subtransmission lines in terms of maintenance planning, and also are employed to make a decision on reliability improvement.