Missouri Code of State Regulations
Title 20 - DEPARTMENT OF COMMERCE AND INSURANCE
Division 4240 - Public Service Commission
Chapter 23 - Electric Utility Operational Standards
Section 20 CSR 4240-23.010 - Electric Utility System Reliability Monitoring and Reporting Submission Requirements

Universal Citation: 20 MO Code of State Regs 4240-23.010

Current through Register Vol. 49, No. 6, March 15, 2024

PURPOSE: This rule establishes reliability monitoring and reporting requirements for electrical corporations.

(1) Information Reported. Commencing with the month following the month in which this rule becomes effective, each electrical corporation (as defined in section 386.020, RSMo) shall accumulate the following information (on a monthly basis):

(A) System Average Interruption Frequency Index (SAIFI), which reflects the average frequency of service interruptions in number of occurrences per customer and is defined as the total number of customer interruptions for the period covered divided by the total number of customers served;

(B) Customer Average Interruption Frequency Index (CAIFI), which reflects the average number of interruptions per customer interrupted and is defined as the total number of customer interruptions for the period covered divided by the total number of customers affected;

(C) System Average Interruption Duration Index (SAIDI), which reflects the average interruption in hours or minutes per customer served for the period covered and is defined as the sum of all customer interruption durations divided by the total number of customers served; and

(D) Customer Average Interruption Duration Index (CAIDI), which reflects the average interruption duration and is defined as the sum of all customer interruption durations divided by the total number of customers interrupted.

(2) Filing of Report. The information required by section (1) shall be filed annually by the last business day of April of the calendar year following the calendar year for which the information was accumulated to the manager of the commission's energy department, or the manager's designee, electronically in tabular and graphical formats.

(3) Adjustment of Data. The information required by section (1) shall be filed both unadjusted and adjusted to exclude major storm events per IEEE Standard 1366-2003, Guide for Electric Power Distribution Reliability Indices.

(4) Scope of Information. The information required by section (1) shall be reported for all Missouri retail electric customers of the electrical corporation.

(5) Interruptions Not to Be Reported. The following interruption causes shall not be included in the calculation of the reliability indices required by section (1):

(A) Interruptions initiated pursuant to the provisions of an interruptible service tariff or contract and affecting only those customers taking electric service under such tariff or contract;

(B) Interruptions due to nonpayment of a bill;

(C) Interruptions due to tampering with service equipment;

(D) Interruptions due to denied access to service equipment located on the affected customer's private property;

(E) Interruptions due to hazardous conditions located on the affected customer's private property;

(F) Interruptions due to a request by the affected customer;

(G) Interruptions due to a request by a law enforcement agency, fire department, other governmental agency responsible for public welfare, or any agency or authority responsible for bulk power system security or reliability; or

(H) Interruptions caused by the failure of a customer's equipment; the operation of a customer's equipment in a manner inconsistent with law, an approved tariff, rule, regulation, or an agreement between the customer and the electrical corporation; or the failure of a customer to take a required action that would have avoided the interruption, such as failing to notify the electrical corporation of an increase in load when required to do so by a tariff or contract.

(6) Worst Performing Circuits. Each electrical corporation shall establish and maintain a program for identifying and analyzing its worst performing circuits during the course of each calendar year. The program shall include, but should not be limited to, an analysis of the top five percent (5%) worst performing circuits used to serve the electrical corporation's Missouri retail electric customers. The worst performing circuits shall be identified and ranked using SAIFI values computed for each circuit, adjusted to exclude major storm events per IEEE Standard 1366-2003, Guide for Electric Power Distribution Reliability Indices and in any other manner chosen by the electrical corporation. The SAIDI value for each circuit shall also be listed.

(7) The information developed in accordance with section (6) shall be reported as part of the annual report required by section (2) and shall also include actions taken (or planned) to improve the performance of the circuits identified in section (6).

(8) Multi-Year Worst Performing Circuit Reporting. If, on or after the time the annual report required by section (7) for calendar year 2011 is filed, a circuit has been on the worst performing circuit list for any two (2) of the three (3) most recent consecutive calendar years, the electrical corporation shall include detailed plans and schedules for improving the performance of that circuit in addition to the other information required by section (7). Such plans and schedules may vary from circuit to circuit based on differences in geography or other local conditions, customer density, and cost considerations.

(9) Reliability Improvement Programs. Each electrical corporation shall transmit to the manager of the energy department of the commission, or the manager's designee, no later than the last business day of December each year: A summary report detailing all programs scheduled for the upcoming calendar year designed to maintain or improve service reliability. The information shall be reported by regional/district/division operating areas, if the electrical corporation's operations are divided into regions/districts/divisions. This report shall include funding levels and the status of each of these programs. The first such report shall be transmitted no later than December 31, 2008.

(10) Residential Subdivision Undergrounding. Where reasonable and consistent with utility easements and applicable law, electrical corporations are to locate all newly installed electrical corporation-owned residential subdivision distribution facilities underground. This provision applies to residential subdivisions with average lots no larger than 0.5 acres. As used in this provision, subdivision distribution facilities refer to terminal poles, manholes, feeder lines, service lines, switchgear, pad-mounted, pole-mounted, or submersible transformers, and pedestals utilized to provide electric service to subdivisions but does not include subtransmission lines and three (3)-phase distribution feeders/backbone circuits (portion of distribution system directly interconnected with distribution substation and prior to the first protective device). If an electric corporation determines that it is not reasonable to place a residential subdivision's distribution facilities underground and the subdivision has average lots no larger than 0.5 acres, the electrical corporation shall maintain records available for Public Service Commission (PSC) inspection to demonstrate why undergrounding was unreasonable.

(11) Comparison of Reliability Metrics. The commission may accumulate the information required by section (1) from the electrical corporations and provide this information to the public. Such disclosure shall include a statement that such indices are affected by customer density, tree density, geography, observed weather, and other factors that may be beyond the control of the electrical corporation. Further, the commission may release comparisons of this data with similar data from other states but in doing so shall include in the release any caveats that would explain differences in the indices. These caveats shall include, but are not limited to, differences in calculation methodologies.

(12) Variances. A variance from a provision of this rule may be granted for good cause shown.

*Original authority: 386.040, RSMo 1939; 386.250, RSMo 1939, amended 1963, 1967, 1977, 1980, 1987, 1988, 1991, 1993, 1995, 1996; 386.310, RSMo 1939, amended 1979, 1989, 1996; 393.130, RSMo 1939, amended 1949, 1967, 2002; and 393.140, RSMo 1939, amended 1949, 1967.

Disclaimer: These regulations may not be the most recent version. Missouri may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
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