Power supply in Darwin’s northern suburbs

23 Dec 2008

October 2008

A damaged circuit breaker at the Casuarina Zone Substation (one of 26 substations) in mid September caused a power outage of 12 hours and affected more than 11,000 customers (about 14% of total customers). 

As the cause of the damage needed to be investigated and new equipment ordered in, temporary repairs were made to get customers’ power back on.

However, a second outage a couple of weeks later resulted in an eight-hour loss of power for about 7,000 customers and further temporary repairs were made.

All zone substations are equipped with spare capacity. The damage at the Casuarina Zone Substation means that while it’s supplying enough power for the area, it has no spare capacity.

To ensure the substation is safe to work in while repairs are being made to it, (plus other equipment running to and from it such as transformers, feeders and powerlines) it maybe necessary to have short duration power outages – these will be advertised.

Power and Water has placed a number of generators around the northern suburbs to provide back up electricity for the area for any longer, necessary repair works and for any other unforseen event.

Questions you may have

How long will it take to repair the Casuarina Zone Substation?

Casuarina Zone Substation switchboard has three sections.  One of these sections is now out of action. A temporary switchboard to replace the damaged section is in Darwin, it is being prepared and should be in service by mid December.  A permanent replacement is being made and is expected to arrive in Darwin in March next year.  This will completely replace all three sections and should be in service by July next year.

Is the power going to be shut down in the northern suburbs?

• No.  However, it maybe necessary to shut power down for a short period if we need to do work on the network (feeders, transformers and power lines) coming into and out of the substation  - we will advertise all planned maintenance.
• Short power outages may occur due to other causes such as bats, trees on power lines or other small faults that happen from time to time across the whole network, not just the Casuarina Zone Substation area.
• If major works are required on the substation that will take quite some time, then this will be advertised and power will be switched over to the generators we have in place across the northern suburbs – we are taking all possible steps to avoid this.

What do the generators do that are place around the northern suburbs?

The large generators housed in shipping containers will provide back up power should we need to take the Casuarina Zone Substation off line for any reason for an extended period of time.  They will not be used unless absolutely necessary.

Will power be rationed?

At this stage you can continue to use power as normal. However, if we need to  run the back up generators for a period of time, we will ask you to reduce power consumption in the affected area.

Will the hospital be okay if the power goes out?

The hospital has its own back up power supply and has a number of large generators on site.

What if I have special medical or other needs?

As part of our normal cyclone preparedness planning, we have a comprehensive list of people who may need assistance or who rely on power for medical reasons. We will ensure these people have adequate access to power.

What should I do if the power goes out?

• Check the newspaper for details of any planned outages to see if your area is listed
• Please wait for 10 minutes before calling our Customer Service line for information on 1800 245 092 – often we can switch around a minor fault and get you back on quite quickly
• Listen to local radio stations for advice – if there is a major fault and we need to go to our back up generators, we will ask radio stations to broadcast a message to customers.