Why VNI West could risk a “cascading collapse”

Electrical experts have warned last week’s storms should be “a wake-up call” for the Allan Government and their power plans for Victoria.

Residents of fire prone Mallacoota were left without power, mobile and NBN for 14 hours last week, after storms hit, after battery backup systems once again failed. Picture: David Caird

Victoria’s rush to rely on a major new interconnector, VNI West, will leave regional communities exposed to life-threatening power and mobile phone outages, sitting in the dark with no way to communicate in the midst of catastrophic storms, floods and bushfires.

Electrical engineer Simon Bartlett and economist Bruce Mountain issued the stark warning after last week’s partial collapse of the grid that left 530,000 Victorian households and businesses without power, labelling it “a wake-up call” the Allan Government must heed.

The outage left one of Victoria’s most bushfire-prone towns, Mallacoota, without power, mobile or NBN coverage for 14 hours, despite Ausnet investing a $7.5m battery backup to the grid and local mobile tower, that failed for the sixth time in six months.

“They talk about resilience, but the technology isn’t up to it,” former Mallacoota and District Recovery Association member Peter Hancock said.

Rather than building greater resilience into the power grid, Professors Bartlett and Mountain argued the Allan Government was turning Victoria into a net importer of renewable energy from NSW, via the VNI West transmission line.

Professor Bartlett said it would take just one of VNI West’s 80m towers to get hit by lightning, be blown over in a storm or short out during a bushfire, for it to cause a “cascading collapse of the power system” that blacked out the state’s south.

“Southern Victoria would immediately lose access to the 6500MW of generating capacity that relies on VNI West,” Prof Bartlett said, who is former University of Tasmania’s Professor of power systems.

“The Heywood and existing (northeast) VNI interconnectors would try to make up the shortfall and immediately overload and trip, leaving the whole of the state south of Ballarat without power.”

Prof Bartlett said restarting the blacked out grid, without coal-fired plants or gas turbines, would take hours or even days, with the Australian Energy Market Operator having “no plan or experience in restarting a primarily renewable power system”.

MOBILE TOWERS FAIL

AEMO reported last Tuesday’s storm tore down hundreds of powerlines and six towers on the two Moorabool to Sydenham 500kV transmission lines that tripped, forcing the disconnection of all four Loy Yang A generating units, plus the Dundonnell Yaloak South wind farms.

Gas turbines were quickly turned on to replace much of the power, but wind-damaged lines across the rest of the state cut power to mobile phone towers, which ran out of battery life within two to four hours.

Telcos reported 486 Telstra and 248 Optus mobile phone sites were down by Wednesday morning, leaving thousands of regional Victorians without power and communication.

Victoria’s east was hardest hit, with towns from Wonthaggi to Yarram and Mallacoota losing power and mobile communication, plus 4831 landlines.

The mobile outage occurred despite calls for greater resilience to be built into the grid and mobile network, after repeated failures in the wake of the 2009 Black Saturday fires, June 2021 storms and 2019-20 summer fires.

The federal government has spent just $38.5m over three years on its Mobile Network Hardening Program, extending the battery life of just 999 of the nation’s 25,892 mobile towers to at least 12 hours.

When asked about the resilience of the mobile network, Telstra regional general manager Steve Tinker said infrastructure inspections and maintenance occurred at 8000 sites in the past six months.

“We’re also upgrading 1000 payphones in disaster-prone areas and deploying 110 generators to augment existing backup power,” he said.

Former Counsel assisting the 2009 Victorian Bushfires Royal Commission Jack Rush said it was astonishing that despite the lessons of past, disasters towns like Mallacoota were once again left without power and communications.

He said the February 7 anniversary of Black Saturday passed by without much comment, yet the lessons are still there for a society that has “an enormous capacity to forget”.

Asked if asked the government would consider an inquiry into disaster preparedness, Premier Jacinta Allan said “through out independent emergency management, general inspector and general emergency management, there is always an overview of the arrangements that have been in place, in terms of both examining the event, and looking at what can be done to prepare for the next one”.

But as with most natural disasters it was regional Victorians who suffered the most, with AusNet reporting that by Wednesday morning last week 285,500 homes and businesses were still without power.

Regional businesses and workers were left idle, many households were unable to cook and were forced to dump frozen food.

Gippsland dairy farmer Steve Ronalds said the violent weather highlighted the vulnerability of agricultural industries when the power is out.

“We’re a vulnerable society,” Mr Ronalds said. “Government needs to get this right. Solar did nothing for us … we have all these things in place but they’re actually useless.”

Nambrok dairy farmer Brett Matthews said a government subsidy of $3000 to $5000 to install the wiring for a generator, would go a long way to help deal with disaster-driven outages.

Victorian Energy Policy Centre director Bruce Mountain said AEMO’s own modelling showed the state would shift from a net exporter of electricity to importing 16 per cent of its needs from NSW by 2030 and 26 per cent by 2035.

But rather than maintaining a diverse range of energy sources, Victoria has stymied onshore gas development and rolled out a Gas Substitution Roadmap in 2022, which Energy Minister Lily D’Ambrosio said would “put gas on the backburner as we help Victorians cut energy bills and halve emissions by 2030”.

Yet gas saved the state last week, with AEMO’s NEM dashboard showing that when Loy Yang A came off line, gas turbines went from producing less than 2 per cent of the state’s power to 30 per cent.