1,000MW electricity demand ‘cliff’ during Melbourne Cup demonstrates resiliency of grid – even with renewables

At about the same time as the running of Victoria’s Melbourne Cup race on Tuesday,  energy market watchers were given a lesson in electricity variability – not the variability of solar and wind generation, but the variability of demand, and how the grid operator handles 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.

5 minute demand NSW

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.

© 2015 Solar Choice Pty Ltd

Giles Parkinson

Giles Parkinson regularly contributes unique content to Solar Choice News. Giles is the founder and editor of clean energy industry news service RenewEconomy. He is a journalist of 30 years experience, a former Business Editor and Deputy Editor of the Financial Review, a columnist for The Bulletin magazine and The Australian, and the founding editor of Climate Spectator.
Giles Parkinson