Power supply — Mundaring–Parkerville
4636. Hon Alison Xamon to the Minister for Energy
(1) How many power supply interruptions have occurred in the Mundaring area in —
(a) 2011;
(b) 2010; and
(c) 2009?
(2) What was the cause of these interruptions?
(3) What is the Government doing to ensure that Mundaring has a reliable, quality power supply?
(4) How many power supply interruptions have occurred in the Parkerville area in —
(a) 2011;
(b) 2010; and
(c) 2009?
(5) What was the cause of these interruptions?
(6) What is the Government doing to ensure that Parkerville has a reliable, quality power supply?
Hon PETER COLLIER replied:
(1) (a) 87
(b) 132
(c) 69
(2) The breakdown of interruption causes is as follows:
2011:
- 25% of outages were due to equipment failures;
- 21% of outages were due to planned outages (maintenance works); and
- 54% of outages were due to a number of circumstances, as outlined in Table 1 of the Attachment to this PQ. [See paper 4008.]
2010:
- 39% of outages were due to planned outages (maintenance works);
- 15% of outages were due to equipment failures; and
- 46% of outages were due to a number of circumstances, as outlined in Table 1 of the Attachment to this PQ. [See paper 4008.]
2009:
- 39% of outages were due to planned outages (maintenance works);
- 19% of outages were due to equipment failures; and
- 42% of outages were due to a number of circumstances, as outlined in Table 1 of the Attachment to this PQ. [See paper 4008.]
(3) Western Power has recently upgraded the Sawyers Valley substation to provide additional network capacity in the area.
The availability of additional network capacity supports the ongoing upgrading of the distribution network in the area. This work will provide greater flexibility to maintain supplies to customers in the event of a supply interruption and is scheduled to be completed over the next two years.
Routine inspection of Western Power assets identifies specific asset issues. Western Power assesses these issues and, based on the condition and location of the asset, prioritises the appropriate maintenance and/or replacement work and timing of that work.
(4) (a) 98
(b) 135
(c) 93
(5) The breakdown of interruption causes is as follows:
2011:
- 43% of outages were due to planned outages (maintenance works);
- 17% of outages were due to equipment failures; and
- 40% of outages were due to a number of circumstances, as outlined in Table 2 of the Attachment to this PQ.
2010:
- 48% of outages were due to planned outages (maintenance works);
- 16% of outages were due to unknown causes; and
- 36% of outages were due to a number of circumstances, as outlined in Table 2 of the Attachment to this PQ.
2009:
- 31% of outages were due to planned outages (maintenance works);
- 22% of outages were due to equipment failures; and
- 47% of outages were due to a number of circumstances, as outlined in Table 2 of the Attachment to this PQ.
(6) Work is underway on expanding the capacity of the Darlington substation, which provides supply to the majority of customers in the Parkerville area. This work is designed to mitigate the failure of equipment and cables due to overloading and is scheduled to be completed by December 2012.
A number of outages were due to defective pole top switchgear. They were all replaced by the manufacturer in October 2011 under warranty.
The routine line patrols of the distribution network supplying the Parkerville area have identified a number of maintenance issues that have been assessed, or are currently being addressed, through the annual works program.