The race that stopped the nation … and electricity demand

Published by

(Note: This story has been updated to reflect the sudden fall in demand was due to outages at the Tomago aluminium smelter).

The anti-renewable lobby love to complain about the intermittency of “variable” renewable energy sources such as wind and solar, saying that it is impossible to manage on a large grid.

But there’s nothing quite so variable as demand … and the grid operator has been handling it just fine, as it has done for decades.

Just minutes before yesterday’s running of the Melbourne Cup there was a 1,000MW “cliff” in the NSW grid, as demand was suddenly lost.

It was first speculated that it was because of disappearing demand as punters took leave of their work stations and work places wound down. Turns out it was a sudden “trip” at the Tomago aluminium smelter which took three pot lines and more than  930MW of demand out of the system

As the graph shows, demand went from more than 8,200MW to less than 7,200MW in the space of five minutes, before gradually recovering over the next hour.

By the way, the big fall in demand on the previous day – though gradual – is an example of the so-called duck curve, where rooftop solar hollows out demand in the middle of the day, once one of the most profitable parts of the day for fossil fuel generators.

One of the differences between wind and solar and fossil fuels is that while the changes in output in wind and solar are quite predictable, sudden outages from coal and gas-fired plants and industrial users are often not.a

Giles Parkinson is founder and editor-in-chief of Renew Economy, and founder and editor of its EV-focused sister site The Driven. He is the co-host of the weekly Energy Insiders Podcast. Giles has been a journalist for more than 40 years and is a former deputy editor of the Australian Financial Review. You can find him on LinkedIn and on Twitter.

Giles Parkinson

Giles Parkinson is founder and editor-in-chief of Renew Economy, and founder and editor of its EV-focused sister site The Driven. He is the co-host of the weekly Energy Insiders Podcast. Giles has been a journalist for more than 40 years and is a former deputy editor of the Australian Financial Review. You can find him on LinkedIn and on Twitter.

Share
Published by

Recent Posts

More wind and batteries raise hopes for electricity bill cuts, but fossil fuel woes could still bite

AER flags cut in cost of electricity for households and businesses across the NEM, as…

19 March 2026

Solar Insiders Podcast: How saving energy can save businesses a fortune

Jonathan Pooch from DETA Consulting on the untapped riches of energy productivity. Plus, news of…

19 March 2026

“The world is changing:” Regulator says consumers won’t be left holding bill for stranded gas networks

AEMC proposes suite of new rules to guide gas companies through the looming network death…

19 March 2026

“Grow your own and buy local”: Networks seek change and flexibility to manage a 100 pct renewable grid

As rooftop solar, home batteries and EV uptake surges, networks seek regulatory change to boost…

19 March 2026

EPBC gives green tick to massive Queensland battery in just 41 days, now for the state

Plans for a massive more than 2 gigawatt-hour battery south of Townsville have been given…

19 March 2026

Regulators will have to be nimble to deal with home battery boom and bigger solar systems, says Kean

CCA chair Matt Kean says regulators will need to be nimble to ensure that households…

19 March 2026