FortisBC Inc. (FortisBC) Application for a Certificate of Public ...

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FortisBC Inc. (FortisBC or the Company)
Application for a Certificate of Public Convenience and Necessity
for the Advanced Metering Infrastructure Project
Response to British Columbia Utilities Commission (BCUC or the Commission)
Information Request (IR) No. 1
5.0 Reference: Description of Existing System
Response:
Exhibit B-1, Tab 3.0, Section 3.1
Failure of existing electromechanical meters
Submission Date:
October 5, 2012
Page 9
“Moreover, new regulations (S-S-06) from Measurement Canada increase the accuracy
requirements for calibrating and testing meters. The approximately 80,000
electromechanical meters in the Company’s metering fleet are expected to fail
compliance sampling at an increased rate, and the expected lifespan of the meter
population will be significantly reduced.” [Ref: B-1, p.18]
“Based on the new S-S-06 regulations, FortisBC anticipates increased failures, shorter
seal extensions, and an increase in compliance sampling costs. As a result, FortisBC
expects an accelerated replacement of approximately 80,000 electro-mechanical meters
and 8,000 digital meters over a 21 year period.” [Ref: B-1, p. 93]
5.1 Please explain the anticipated failure rate for the electro-mechanical meters, and
provide evidence to support the explanation. At what future date will all the
existing 80,000 electromechanical meters have failed statistical testing and
require replacement?
A model was created to simulate and predict the useful life of the existing FortisBC electromechanical
meter population. This model assumed reasonable and conservative failure rates
based on the recommendations of our third party meter shop. The failure rates used in the
model are consistent with rates observed by the meter shop when using SS-06 guidelines in
preliminary sample testing. The model assumes that as a meter ages, the likelihood of a failure
increases.
For SS-06 there are 5 levels that a meter under compliance testing can attempt to achieve
(target). This level corresponds to the maximum seal extension the meter is eligible for and is
based on the previous extension period and the original seal length. For each decreasing level,
the requirements to pass become more stringent, but the seal extensions become longer.
For its model, FortisBC determined the highest level each meter lot could target under SS-06
and then simulated compliance testing to determine pass/fail and the resulting seal extension
length.
FortisBC used the following probabilities for determining which SS-06 level was obtained by
each meter lot during simulated sampling activities: