Since the major outage in 2015, there have been six smaller outages on Scotland Island and West Pittwater. These were associated with storm events or vegetation coming into contact with our overhead network and were not been related to the submarine power cables. Access and safety issues have also been challenging during outages in both locations. This has contributed to the time taken to restore power.
Ausgrid has been progressing feasibility and design studies and working with industry experts to determine the best solution for each community. As a project team, we have assessed a number of options and are now moving forward. These solutions aim to minimise the impact of electrical outages to the residents and businesses of Scotland Island and West Pittwater.
The investigations concluded that two different approaches are required for Scotland Island and West Pittwater due to the layout and design of the existing electricity network in each of these areas. West Pittwater has a linear network arrangement and Scotland Island has a circular one.
A number of project scenarios were assessed for each location (including the original cable loop) to arrive at the proposed solutions.
Scotland Island
Ausgrid’s proposed solution is to use Horizontal Directional Drilling (HDD) to create a bore from Church Point to Carol’s Wharf, Scotland Island which will house a new electricity cable. Both the new and existing cable will be in service at the same time in order to minimise the impact of a failure to a single cable. The new cable will lie in a conduit (pipe) below the ocean bed rather than on the ocean floor as the current cable does. This will minimise the risk of impact or damage.
As part of the design for the HDD bore, Ausgrid is considering future energy requirements for the Island and the possibility of including NBN cables or fibres.
Work is expected to start in April 2019 and be completed by the end of July 2019. Further project information including construction details, will be sent to residents when finalised.
West Pittwater
The linear nature of the network at West Pittwater means there is no traditional ‘poles and wires’ solution that can address all the types of outages faced in the area. As such, Ausgrid is proposing to install a hybrid solution to address the various types of network outages being experienced.
Details of the final solution will be provided to individual households after consultation with market experts. However, based on preliminary consultation the hybrid solution will most likely be a combination of technologies such as household batteries and solar, plus a hybrid community generator. Ausgrid will be seeking expert market input in early 2019.
Home Energy Audits
Ausgrid commissioned local company, Your Energy Friend to undertake home energy audits for interested at West Pittwater. The purpose of the audits was to understand local conditions and household energy use to assist in assessing alternative options. These options included demand management, energy efficiencies, generation and storage options.
Summary finding from the audits were:
- Based on the opinion of the auditor and home occupier, approximately 80% of the surveyed properties have some level of solar access or generation potential with less than 10% of properties with solar PV currently installed. This opportunity assumes generation greater than 2-3 hours per day as a minimum, but will need to be qualified with a solar specialist. Areas assessed included the building, but also yard, jetty and infrastructure space.
- Almost all households audited indicated a support for or an interest in installing household battery storage systems.
- Small appliance ownership was high overall, with an unusually high ownership of heated towel racks and bathroom floor heating, with some systems set to operate 24 hours year-round leading to considerable electricity consumption.
- An opportunity exists to reduce power usage with remote controlled power eliminators to switch off small appliances that are using high levels of stand-by power.
- Water heater replacement/thermal set point tuning appears to be a prospective opportunity in the
supply area, with such a large number of inefficient electric hot water systems, many of which were observed to have inappropriately high temperature thermal set points.
- The dominant driver of electricity consumption appears to be water heating, with a significant number of electric hot water systems in use.
To view the full summary report click on the link below.
