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ERMU's 2003 CAIDI is 70.03. We do not as yet have a feel for this number if it is good, <br /> average, or bad. <br /> 3. SAIDI (system average interruption duration index) <br /> This is defined as the average interruption duration for customers served during a <br /> specified time period. It is determined by summing the customer-minutes off for each <br /> interruption during a specified time period and dividing the sum by the average number <br /> of customers served during that period. The unit is minutes. This index enables the <br /> utility to report how many minutes customers would have been out of service if all <br /> customers were out at one time. <br /> ERMU's SAIDI is 5.46. We do not as yet have a feel for this number if it is good, <br /> average, or bad. <br /> 4. SAIFI (system average interruption frequency index) <br /> This is defined as the average number of times that a customer is interrupted during a <br /> specified time period. It is determined by dividing the total number of customers <br /> interrupted in a time period by the average number of customers served. The resulting <br /> unit is "interruptions per customer". Separate SAIFI indexes are sometimes calculated <br /> for long and for short interruptions. <br /> ERMU's 2003 SAIFI is .78 with GRE's transmission outage and .051 w/o GRE <br /> transmission outage. .051 equals to a customer will experience an electric outage every <br /> 19.6 years. This appears to be a very good number. <br /> Another statistic staff gets concerned about is the overage length of any outage. ERMU's <br /> 2003 average length of outage is 101.37 minutes. Electric utilities with a high percent of <br /> underground facilities will exhibit higher length of outage times than electric utilities <br /> with high percent of overhead facilities. We are currently trying to find these statistics <br /> from other electric utilities. <br /> Staff has reviewed these statistics in detail to find ways to improve. My experience tells <br /> my these statistics are very complementary to ERMU. Glenn Sundeen and his <br /> department continue to do an outstanding job in constructing, operating and maintaining <br /> an electrical system particularly in a fast growing area. <br />