Victorian network company Powercor will offer 17 standalone power systems (SAPS) to customers at the very edge of their network, giving them the option to switch to a mix of solar, batteries and back-up generation – and eventually to retire their powerline permanently.
The powerlines in question, Single Wire Earth Return (SWER) lines, were rolled out across remote and rural parts of Australia in the 1950s and 1960s to support homes and businesses that were further away from the grid.
SWER lines are 12.7kV electrical lines made up of a single conductor supported by single insulators on poles, with wide spans between each pole – on average about 2.5 poles per kilometre, versus conventional two-wire or three-wire lines, which require seven poles per kilometre.
They’ve been great for providing power across long distances, with the earth itself acting as the return path for the electrical current, eliminating the need for a separate neutral wire.
But SWER lines are less reliable than their multi-wire counterparts, vulnerable to severe weather conditions and more expensive and difficult to maintain and upgrade.
Regional and rural customers of Powercor incur on average four times more minutes off-supply than urban customers.
And SWER lines may also carry a higher bushfire risk, particularly if they are not appropriately maintained.
The 17 sites will be provided with a range of options including a mix of solar, battery storage and back-up generators, but Powercor said it will leave the original SWER lines in place for a short time to ensure the system is satisfactory before the lines are retired completely.
Powercor is not the first energy provider to the party on this, but it is the first time SAPS will be offered as a viable alternative to outdated powerlines by a privately owned energy provider in Victoria.
In 2019, Western Australia state-owned network Horizon Power announced it would install 17 new SAPS on properties situated on the fringes of the grid, cutting down 64 kilometres of unreliable wiring.
It’s a move network companies have been actively advocating for since at least 2017, pointing out that it’s a win-win for reliable affordable energy.
That’s because the supply and maintenance of electricity to remote and regional communities costs billions of dollars in cross subsidies, with the bill footed by all consumers, meanwhile regional and remote customers live with unreliable power supply compared to their urban and suburban counterparts.
“All customers no matter where they live are more reliant on electricity than ever before so it’s essential we are able to deliver the power they need,” said Powercor’s General Manager of regulation, Renate Vogt.
“Our tailored package is designed to lift reliability and capacity for regional and rural customers, bridging the gap between city and country customers’ access to electrification opportunities.
“Upgrading the SWER network in targeted areas will support regional businesses grow and invest in larger facilities and operations, driving economic growth.”
The move to provide standalone power systems to the 17 identified sites is part of a broader package that includes upgrading 606 kilometres of SWER to 22kV, three-phase supply across 44 areas that the company has identified as having SWER lines at risk of reaching capacity.
Upgrades to those 44 sites will benefit 1,310 customers in rural areas of the Wimmera, the Goulburn Valley, the South West and the Macedon Ranges.
According to Powercor, 74 per cent of its customers supported a $50 million SWER upgrade program that would increase residential bills by $0.61 per year.
These upgrades are all part of a $3.6 billion “regulatory reset” for 2026-2031 that Powercor has proposed to shore up the electricity system of the future in Victoria’s West.
The proposal, submitted to the Australian Energy Regulator (AER) for approval, includes changes such as allowing flexible exports for rooftop solar, investing $81 million in regional and rural customers, $90 million to manage demand in high growth corridors in Melbourne’s west, and $1.3 billion to maintain the company’s existing assets.
Powercor says these various upgrades should cost the consumer an extra $3 per year on their power bills.
