They say that lightning never strikes twice. But on August 25 last year, a single lightning strike managed to take out two major circuits on the main transmission line linking NSW and Queensland.
The impact was almost immediate and felt across Australia’s main grid. It caused load-shedding at a scale that made the much-talked-about load shedding in Victoria in January’s heat wave look comparatively small beer.
We reported the events at the time, noting the irony of the Tesla big battery holding together the grid on the very first full day of work for the new prime minister, Scott Morrison, the man who had spent so much time promoting coal and ridiculing new technologies like the big battery.
Our initial report has now been underscored by a detailed study from the Australian Energy Market Operator, which looked at why more than 1,190MW of load was shed in three states, why Queensland operated for nearly an hour and a half in an insecure state that could have gone pear-shaped very quickly, and why renewables-dominated South Australia had the most secure grid during the events.
The report underlines a few important points.
One is that the Tesla big battery, again, proved itself to be an exceptionally valuable asset in the face of such events.
It was the quickest to respond and showed a versatility unmatched by any other asset, and its efforts ensured that South Australia’s was the only state grid not to suffer widespread losses or operate in an insecure state, despite its high share of renewables.
Point two is that Australia’s aging and slow-moving legacy assets reacted poorly, and it is increasingly clear that they are going to create headaches for the market operator as it manages the energy transition, and seeks to perform the energy equivalent of the shift from analog to digital.
Three: new technologies such as wind farms and rooftop solar inverters are also throwing curve balls, with unexpected responses to different situations.
And four; the market operator and the rule-maker need to act quickly and decisively to bring in rules that are useful to the latest technology, and not those of the last century.