Rule 4901:1-10-10 | Distribution system reliability.
(A) General. This rule prescribes the measurement of each electric utility's service reliability, the development of minimum performance standards for such reliability, and the reporting of performance against the established standards.
(B) Service reliability indices and minimum performance standards.
(1) The service reliability indices are as follows:
"CAIDI," or the customer average interruption duration index, represents the average interruption duration or average time to restore service per interrupted customer. CAIDI is expressed by the following formula:
CAIDI equals sum of customer interruption durations divided by total number of customer interruptions
"SAIFI," or the system average interruption frequency index, represents the average number of interruptions per customer. SAIFI is expressed by the following formula:
SAIFI equals total number of customer interruptions divided by total number of customers served
(2) Each electric utility in this state shall file with the commission an application to establish company-specific minimum reliability performance standards.
(3) Applications for approval of a reliability performance standard shall include:
(a) A proposed methodology for establishing reliability standards.
(b) A proposed company-specific reliability performance standard for each service reliability index based on the proposed methodology.
(c) Supporting justification for the proposed methodology and each resulting performance standard.
(4) Supporting justification for the proposed methodology and each resulting performance standard.
(a) Performance standards should reflect historical system performance, system design, technological advancements, service area geography, customer perception survey results as defined in paragraph (B)(4)(b) of this rule, and other relevant factors.
(b) Each electric utility shall periodically (no less than every three years) conduct a customer perception survey. The survey results shall also be used as an input to the methodology for calculating new performance standards. The survey shall be paid for by the electric utility and shall be conducted under staff oversight. The objective of the survey is to measure customer perceptions, including, but not limited to expectations of electric service reliability in terms of the service reliability indices defined in paragraph (B)(1) of this rule.
(c) Performance data during major events and transmission outages shall be excluded from the calculation of the indices, proposed standards, and any revised performance standards, as set forth in paragraph (B) of this rule.
(5) Unless otherwise ordered by the commission, legal director, deputy legal director, or attorney examiner, the following procedural schedule shall apply:
(a) Upon the filing of an application, the commission, legal director, deputy legal director, or an attorney examiner will schedule a technical conference. The purpose of the technical conference is to allow interested persons an opportunity to better understand the electric utility's application. The electric utility will have the necessary personnel in attendance at this conference so as to explain, among other things, the filing, the work papers and the manner in which methodologies and resulting performance standards were devised. The conference will be held at the commission offices.
(b) Within twenty calendar days after the technical conference, any person may file comments.
(c) Within thirty calendar days after the technical conference, the commission's staff may file comments.
(d) Within fifty calendar days after the technical conference, any person may file a response to the comments.
(e) If the commission schedules a hearing, interested persons wishing to participate in the hearing may file a motion to intervene no later than thirty calendar days after the issuance of the entry scheduling the hearing, unless ordered otherwise by the commission, legal director, deputy legal director, or attorney examiner. This rule does not prohibit the filing of a motion to intervene and conducting discovery prior to the issuance of an entry scheduling a hearing.
(6) An electric utility may request to revise its authorized performance standards by filing its revisions and supporting justification for such revisions with the commission for approval pursuant to paragraph (B)(6) of this rule, unless otherwise ordered by the commission, legal director, deputy legal director, or attorney examiner.
(7) The authorized performance standards approved for an electric utility shall remain in place until superseded by revised standards as approved by the commission.
(C) Annual report. Each electric utility shall file with the commission an annual report by March thirty-first of each year. That annual report shall include the following information regarding the previous calendar year:
(1) Annual performance and supporting data for each service reliability index set forth in paragraph (B) of this rule both with and without exclusions for major events and transmission outages. Supporting data includes, for example, the number of customers served, the number of customer interruptions, the number of customer minutes interrupted, SAIFI data for a major event, CAIDI data for a major event, information concerning a transmission interruption, and a listing of distribution circuits interrupted during a transmission interruption.
(2) Performance on the same indices during major events and transmission outages, reported in separate categories with their respective supporting data.
(3) Data for the total number of sustained outages, customers interrupted, and customer minutes interrupted for each outage cause code, all of which shall be reported in the following versions:
(a) Data excluding major events and transmission outages.
(b) Data for major events only.
(c) Data for transmission outages only.
(4) Each electric utility shall file the annual report required by paragraph (C) of this rule in an electronic form prescribed by the commission or its staff.
(D) If the annual performance of an electric utility does not meet the electric utility's performance standard for any index, the electric utility shall file with the commission an action plan, by March thirty-first of the year following the year when the standard was missed.
The action plan shall include the following:
(1) Factors which contributed to the actual performance level for that index.
(2) A proposal for improving performance to a level that meets or exceeds the performance standards authorized for each missed reliability index, including each action taken or planned to be taken, and the anticipated completion date.
(E) Failure to meet the same performance standard for two consecutive years shall constitute a violation of this rule.
Last updated April 8, 2024 at 8:31 AM
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