Incrementing Averages, a Methodology for Showing the Impact of OMS Addition on Reliability Indices

Since performance based rate making began in earnest in the 1990's, a method to identify the impact of changing to a new outage management system (OMS) on reliability indices has been sought. As companies become more sophisticated in their data collection and data processing efforts, using new systems and different processes has resulted in more accurate resulting metrics, often leading to a perceived worsening of the company's reliability performance. In addition, there is the underlying concern that new rate structures will provide incentives to companies to perform less maintenance. This paper presents a novel approach to determining the impact of system changes, whether a new OMS or maintenance strategy, on reliability indices. In doing so, it will show both the impact of system changes as well as degradation in performance, if either, or both are present