E-35—Policy on the retention of metering information and legally relevant interval data used in billing applications

The copy of this document located on Measurement Canada's website is considered to be the controlled copy.

Category: Electricity
Bulletin: E-35
Issue Date:
Effective Date:


Table of contents


1.0 Purpose

The purpose of this bulletin is to provide a policy on the application of the requirements of section 11 of the Electricity and Gas Inspection Regulations regarding the retention of metering information and legally relevant interval data used in billing applications.

2.0 Scope

This bulletin applies to records retained by the meter owner of legally relevant measurement data used to establish the basis of a charge for the sale of electricity supplied.

3.0 References

3.1 Electricity and Gas Inspection Act (R.S. 1985, c. E-4), section 3

3.2 Electricity and Gas Inspection Regulations (SOR/86-131), section 11

4.0 Terminology

Interval data
Contiguous time stamped legally relevant data that is stored in a data recorder. The interval data may be used to produce electricity demand processed legal units of measure values or where totalizing of energy data is required.
Legally relevant data
Information that is approved and verified to be representative of a legal unit of measure.
Processed legal unit of measure value
A legal unit of measure value that has been derived outside a source meter from legally relevant data or from source legal unit of measure values, incorporating recognized units of measure, data multipliers and/or installation multipliers (as applicable), through a mathematical algorithm.
Source legal unit of measure value
A source legal unit of measure value that is capable of being indicated by a source meter.

5.0 Background

The electricity industry has raised concerns regarding the amount of measurement data that is required to be retained by meter owners subject to interval billing applications pursuant to the Act and Regulations.

In summary, subsection 16(2) of the Act requires meter owners to keep records as prescribed in the Regulations. Paragraphs 11(2)(m) and 11(7)(a) of the Regulations require that, for each billing period, the metering information used by the owner in establishing a charge be retained for at least 12 months after the meter ceases to be used.

The above legal requirements were established at a time when electricity utilities used monthly or bi-monthly meter readings for billing customers. The amount of measurement data obtained and methods used for retention were relatively easy for meter owners to manage and administer during those years. In present day, where five-minute demand periods and real-time interval data are used for billing, these legal requirements become significantly more burdensome due to the high volume of data acquired. In addition, maintaining and transitioning that amount of data across multiple computer system platforms over a meter's life greatly exacerbates the difficulties of meter data retention. In addition to data memory issues, there are also challenges with meter data transfer, formatting and communication issues with successive computer system platforms.

In recognition of the growing technical and financial challenges facing electricity suppliers using interval data billing practices, Measurement Canada is establishing a policy that interprets the legislative requirements for the retention of measurement data in these applications. As the Regulations do not provide retention criteria for specific five-minute time-stamped interval data, the policy will limit the retention of interval data to two calendar years. Nevertheless, as the Regulations require that cumulative measurement data be retained for each billing period, meter owners will still be required to retain such data for up to one year following the date on which the meter ceased to be used. Any dispute investigations involving measurement data that extends beyond two years will mean that any errors found, would be applied on the basis of the cumulative measurement data retained in the meter owner's records.

6.0 Policy

6.1 For the purpose of administering the requirements of paragraph 11(2)(m) and subsection 11(7) of the Regulations, the following records of legally relevant data and interval data shall be kept by the meter owner/contractor pursuant to the specified conditions:

  1. subject to 6.1(c), legally relevant metering data, including all the interval data used for each 5- to 15-minute interval, for each billing period, shall be retained and made readily accessible by the owner/contractor for a minimum of two calendar years;
  2. cumulative legally relevant data shall be made readily accessible by the owner/contractor for the purpose of consumer review; and
  3. in addition to 6.1(a), the cumulative legally relevant data for each billing period (e.g. monthly) shall be kept by the owner/contractor for a period of at least 12 months after the date the meter ceased to be used.

Note: The cumulative data described in 6.1(c) does not include all the legally relevant data from each 5- to 15-minute interval beyond the two-calendar-year period prescribed in 6.1(a).