High voltage interruptions and causes

	20 October - 27 October 2025	From 1 January 2025
Number of high voltage interruptions	158	2560
Cause of interruption	% of total	% of total
Weather (including lightning, vegetation, wind blown debris)	34	29
Third Party (for example vehicles hitting SA Power Networks equipment, vandalism, tree felling, our underground cables being damaged during excavation by external parties)	1	6
Operational (for safety reasons our equipment is set up to act like a residential safety switch. The system 'trips' when something abnormal has caused it to flash over ie unexpected electrical or mechanical transients)	1	1
Animals (for safety reasons our equipment is set up to act like a residential safety switch. The system 'trips' when something abnormal has caused it to flash over, ie birds, possums, rats and other animals)	4	8
Equipment (when our equipment has been damaged and needs to be repaired)	27	27
Unknown (is when the cause is inconclusive at the time of the report, the cause may be determined at a later date, or there is no evidence of the cause i.e. a transient fault)	30	26
Other (causes that do not fit into the above categories e.g. customer's plant, other faults that cause SA Power Networks equipment to operate)	3	3

 

Please note:

• This is preliminary data only, and is based on the number of events that have occurred.
• Official figures are published in ESCOSA's Quarterly and Annual Operational Performance Reports.
• Data does not include:
  • Low Voltage interruptions
  • planned interruptions
  • momentary interruptions (ie. a momentary interruption is now a duration of 3 minutes or less).