This material was originally developed for our
Technical Insights Workshop series held from
June to August 2014. These workshops brought
together representatives of our key customer
groups, to discuss customers’ views and
preferences in the complex network decisions
we make on their behalf.
Following positive feedback from attendees, we
have used the workshop material as the basis
of a series of stand-alone information briefs with
the aim of building understanding about our
business and the services we provide.
.
Our customers see safety as one of the most
important issues related to our electricity networks.
At least half of the customers interviewed are
interested in understanding how network
investment affects prices.
Of those customers who have some understanding
of AusNet Services’ role, the majority (>70%) agree This Energy Insights document examines network
that we are committed to safety and act
safety and bushfire mitigation. We look at our
responsibly.
network operating environment, the way we
Around 50% of our customers believe more money manage network safety risks and how increased
expenditure is making this network safer. We also
needs to be spent to make the energy distribution
summarise the future direction of our enhanced
network safer.
safety program.
An AusNet Services’ crew at work. Regular inspections and
maintenance are key aspects of network safety.
Community expectations about safety are
provide benefits in terms of reduced risk, their cost
increasing, particularly as a consequence of the
is significant and this must be considered in the
2009 bushfires and subsequent Victorian Bushfires context of affordability to customers.
Royal Commission.
The Victorian Electricity Safety Act mandates
Electricity assets, particularly overhead powerlines Electricity Safety Management Schemes for major
lines are inherently risky. However, they are widely electricity companies. All schemes require risk
used as they are a cost efficient means of
assessment and management of residual risks to a
developing an electricity distribution network.
level that is as low as practicable. The AusNet
Overhead powerlines comprise 86% of our total
Services electricity network has some unique
network line length of 49,000km. The key network characteristics to which our safety program is
safety risks include bushfire and electric shock or
tailored.
electrocution. While underground powerlines
AusNet Services’ electricity distribution network (shown in blue)
Key facts about our electricity distribution network
Our electricity distribution network comprises an 80,000km2 service
area
95% of our total powerline length is rural network
5% of our total powerline length is urban network
39,359 km of overhead lines
406,264 powerpoles
676,316 customers
Approximately 14,000 network faults repaired each year
Bushfire risk across Australia
Source: Blong, R.J, Sinai, D and Packham.
The above map shows bushfire risk across
Australia. High, very high and extreme risk areas
occur in densely forested or bush areas. Ninety five
per cent of our network services rural customers
and a significant proportion of that is in densely
forested or bush areas.
The map below shows Australian population
density. It can be seen that the combination of high
bushfire risk and population density makes our
geographical location and associated safety
challenges unique.
Australian Population Density
Addressing network safety challenges
The diagram below shows how we are addressing
safety challenges through a combination of
business as usual activities (to maintain existing
1
risk) and enhanced safety programs (to further
reduce risk).
_
2
3
How we develop targeted safety programs
Our safety programs are developed through the three step process shown below.
1.
Identify network incident trends.
2.
Analyse individual causes of failures and the potential consequences of incidents.
3.
Development of cost effective safety programs to reduce or manage network risk.
Network incidents with potential to cause fire and electric shock,
April 2008 – March 2014
The above chart shows network incidents by asset category. These incidents serve
as ‘lead indicators.’ They do not necessarily result in fire and/or electric shock, but
have the potential to cause such events. Condition-based assessment and
predictive asset replacement are used to address these incidents.
Causes of asset and ground fires 2006-2014
The above pie chart shows a breakdown of fire
starts by cause between 2006 and 2014. It can be
seen that the most common causes of asset and
ground fires during this period were high voltage
fuse failure and crossarm failure.
Asset fires are fires that occur within network
infrastructure such as fuses or crossarms and
remain within the infrastructure. Ground fires
originate within network infrastructure and migrate
to the surrounding environment. As asset fires may
lead to ground fires, they are recorded and
included in total fire starts.
Identification of the causes of fire incidents has
resulted in the establishment of an enhanced
network safety strategy that prioritises network
investment to mitigate fire risk.
This strategy is supported through the Australian
Energy Regulator’s ‘F-factor’ scheme introduced
post the 2009 Victorian Bushfires Royal
Commission (VBRC). This regulatory scheme
consists of a financial incentive mechanism with
the objective of reducing network-related fire
incidents.
How do we prioritise locations for safety expenditure?
With almost 40,000km of overhead lines and a
service area of around 80,000 square km, the
AusNet Services network faces unique challenges.
Within our network, risk levels, and the
consequences of incidents, are closely tied to
geographic location.
Subsequent to the 2009 VBRC, the Powerline
Bushfire Safety Taskforce, established by the
Victorian State Government, developed a ‘fire loss
consequence’ model with support from the Fire
Services Commissioner. The government continues
to administer the development of the modelling
which is utilised in the prioritisation and targeting of
distribution network investment.
Implementing VBRC recommendations
The 2009 VBRC made seven electricity
recommendations relating to the electricity industry.
The table below lists those recommendations and
the status of implementation by AusNet Services.
These measures reflect a significant step-up in
safety-related programs in high bushfire risk areas,
over and above our business as usual asset
maintenance program.
VBRC recommendations and implementation status
Safety related expenditure is a driver of price increases
$Mill
Forecast
expenditure 2014
The above chart shows safety related expenditure since 2009. In this period
AusNet Services has invested a total of more than $291 million in targeted
safety programs, in addition to our general maintenance and inspection
programs. While this expenditure is a significant driver of price increases,
it is having a positive impact, as the next section shows.
This section shows how increased safety
expenditure is having a positive impact on network
safety. The first chart (i) shows a major decrease in
crossarm-related asset and ground fires as a result
of replacement of 45,000 high voltage wooden
crossarms. The second chart (ii) shows a significant
decrease in high voltage fuse-related asset and
ground fires as a result of replacement of 30,000
high voltage fuses.
The third chart (iii) shows a significant decrease in
reported electric shock incidents, resulting from our
program of targeted service cable replacement.
Smart meters have enabled more efficient
diagnosis of deteriorated service cables.
Since 2013, we have identified and removed 1,000
safety hazards that may have resulted in electric
shocks to customers. (Note: ‘Fire starts’ do not
necessarily lead to major fire events).
i. Fewer crossarm-related asset and ground fires
Number of
crossarm
related fires
(asset or
ground).
ii. Fewer high voltage fuse related-asset and ground fires
Number of
high voltage
fuse related
fires (asset or
ground).
iii. Fewer electric shock incidents
Number of
electric shock
incidents per
month.
vi. Fewer incidents with fire or shock potential
Number of
incidents
with fire or
shock
potential
The above chart shows a decrease in network
incidents that have the potential to start fires or
cause electric shocks.
By reducing potential fire incidents, we are reducing
the risk of fire starts and enhancing community
safety.
v. Fewer asset and ground fires
Number of
asset and
ground
fires
An incentive scheme created by the Australian
Energy Regulator also provides a financial
incentive for electricity distribution businesses to
reduce fire starts by either rewarding or penalising
them according to the number of fires.
The above chart shows that AusNet Services has
reduced fire starts to well below the regulatory
benchmark since 2009. We have developed a
sophisticated approach to managing network
safety and the effectiveness of this approach can
be seen in results such as those above and on the
previous page.
Project area
Largely
Completed
Ongoing
Emerging
2010-2015
2016-2020
Crossarm Replacement
Insulator Replacement
SWER & 3-Phase ACR Replacement
Relay Replacement
Line Clearance Survey
Line Clearance Construction
Conductor Replacement
High Voltage Fuses
Animal / Bird Proofing
Vibration Dampers & Armour Rods
Ground Fault Neutraliser Technology
Advanced Protection and Control
FOLCB / Isolators
Bare wire powerline replacement
The above table represents the progress of project
areas within our enhanced safety program. In the
period between 2010 and 2015, we commenced 11
separate project areas and completed five, with six
continuing into the next regulatory period. Between
2016 and 2020, we expect to develop three
emerging areas to further reduce risk and increase
community safety.
Vegetation management
Vegetation management is an important AusNet
Services safety program. Through regular
inspections, pruning, clearing and education, we
work to reduce the risk related to this significant
bushfire factor.
Vegetation can also damage electrical assets and
interrupt electricity supply.
1. Protecting communities is of critical importance
2. AusNet Services’ network operates in a unique geographical
location
3. Safety expenditure is a significant driver of price increases
4. We have developed a sophisticated approach to managing safety
5. Our enhanced safety programs have delivered demonstrated
improvements