Reliability Planning at Dominion

Summary form only given: Dominion approaches reliability planning with a primary focus on SAIDI. The various SAIDI management programs can be described along one of two main paths - traditional and non-traditional. In the more traditional vein, an assessment is made of whether SAIDI is under control or not. These analyses are drilled down to office and circuit levels. The primary causes of outages are filtered into controllable and non-controllable causes and the controllable list is used to guide the future reliability programs. In the non-traditional sense, there are two principal categories to explore. The first type is infrastructure related. Our worst circuit list initiates a fresh look at what can be done to improve the poorer performers. In addition, there are older segments of our system that have multiple strikes against them small wire, lower voltage, old transformers, obsolete equipment, etc. The SAIDI hit is generally not that great because of fewer customers served from lower voltage systems, but the number of outages ties up resources. Both types of infrastructure related programs are presently being implemented. The second group stems from the fact that reliability indices are customer weighted and, as a result, repeat outages to small groups of customers are largely ignored. To this end, Dominion has developed a Customer Experience Index and has implemented reliability programs aimed at improving reliability for this segment. This paper provides details of what constitutes a good reliability planning process at Dominion.