What can be learnt from Victoria's severe storm event?

Experts from Monash University have offered insights into the extreme disruption of Victoria’s power system last week due to a severe storm.

On Tuesday, 13 February, AEMO reported that a significant power system event had occurred in Victoria in the early afternoon. The Moorabool to Sydenham 500-kilovolt transmission lines had tripped, multiple generators disconnected from the grid and a huge number of consumers experienced a loss of electricity supply.

To keep the power system secure, AEMO directed AusNet Services to enact ‘load shedding’ — the last-resort process of temporarily cutting off parts of the system so as to protect system security and prevent long-term damage to system infrastructure.

At peak of the event, 530,000 homes and businesses suffered from a loss of power.

With strong winds and fallen trees estimated to have damaged hundreds of powerlines and power poles, network crews battled challenging weather conditions, unstable trees and access issues to repair damaged powerlines and critical energy infrastructure.

Given the widespread damage, AEMO estimated that it might take weeks to restore the system completely.

Describing the storm’s impact, Associate Professor Roger Dargaville, Director of the Monash Energy Institute, said that along with the many localised power outages due to low-voltage powerlines being damaged, several towers supporting the parallel 500 kV lines between Melbourne and Geelong were destroyed.

“The effect of losing that vital infrastructure was to ‘trip off’ the Loy Yang A power station,” Dargaville said.

“As in the case of South Australia in 2016, we have seen instances where an entire state’s grid was impacted leaving everyone statewide without power. The fact that the Victorian grid did not completely fail is a testament to the resilience in the system and the safety mechanisms in place to protect vital infrastructure,” he continued.

Dargaville said that distributed renewable energy systems were on the one hand more vulnerable, due to having more infrastructure spread over wider areas, but on the other hand offered additional resilience, as losses of individual powerlines don’t have the same impact as losing large centralised power stations.

“As a result of climate change we are bound to have more wild weather conditions in the future and our energy systems must learn to adapt and grapple with such situations more often. Additional system security measures such as redundancy, ie, extra energy generation beyond just what is forecast to be required, and fast response storage technologies will help make the system more robust,” he advised.

Australia’s gas lobby was eager to make the point that there were no outages or faults to Victoria’s underground pipeline or gas distribution networks.

“Victoria’s gas generators prevented a worse outcome from occurring,” said Australian Pipelines and Gas Association (APGA) Chief Executive Steve Davies.

“There aren’t any low-cost alternatives that can rapidly provide a third of a state’s electricity in response to an emergency event. We must secure this future capability by including gas in the Capacity Investment Scheme.

“As the energy transition progresses, there’s no guarantee gas will be there when it’s needed in future as it was on Tuesday if it continues to be excluded from energy investment policies,” Davies cautioned, adding that in future, renewable gas could be used in the pre-existing, underground network.

Associate Professor Behrooz Bahrani, from Electrical and Computer Systems Engineering at Monash’s Faculty of Engineering, said that the severe storm, amplified by a global temperature increase of 1.5°C, underscored the need to integrate renewable energy into Australia’s grid.

“Building on the urgency highlighted by Victoria’s power outages, it’s clear that accelerating the adoption of renewables is not just an environmental imperative but a strategic necessity for energy security. The transition to green energy sources is key to mitigating future climate risks and ensuring a sustainable power supply,” Bahrani said.

“The challenge now is not only to embrace renewables but to master the complexities of integrating them into our existing grid. This involves advancing smart grid technologies to enhance flexibility and reliability.

As we move forward from Victoria’s storm event, our focus must be on creating a robust, adaptable energy infrastructure capable of surviving the impacts of climate change while supporting our transition to a low-carbon future,” he concluded.

Image caption: The intense storm passed over Richmond in Melbourne on 13 February 2024. Image credit: iStock.com/FiledIMAGE