Well-being reliability worth indices due to different customer outage cost functions

The evaluation of the costs and benefits of competing investments is a standard practice in power system planning. Customer outage costs, which serve as surrogates for the perceived worth of supply reliability, have been determined, among others, for several provinces and countries as diverse as Canada, United Kingdom, Nepal and Thailand. This paper uses the well-being framework to evaluate the societal worth of electric service reliability in subtransmission systems associated with the outage cost functions of the above four systems. System well-being is defined in terms of the system being in the healthy, marginal, and at risk states, hence combining the deterministic and probabilistic approaches into a single framework. Reliability worth indices such as expected cost of interruptions (ECOST) and interrupted energy assessment rate (IEAR) are evaluated. The concepts are illustrated by application to a small but comprehensive reliability test system designated RBTS.