Sydney risks blackouts as heat soars and coal power plants falter

Sydneysiders were asked to reduce energy usage on Wednesday afternoon and evening to avoid blackouts on the hottest November day since 2020 in a stark demonstration of the increasing unreliability of the ageing coal power fleet.

Four of the 12 power-generation units at the state’s coal power plants were offline for maintenance or breakdowns, while demand soared because of the need for air-conditioning as the temperature neared 40 degrees in parts of the city.

Piping-hot tracks and equipment caused Sydney Trains to reduce speeds on the rail network by up to 10km/h in the west and south-west of the city between noon and 8pm to conserve energy and reduce fire risk.

The Australian Energy Market Operator (AEMO) had warned of a heightened risk of electricity blackouts for NSW from 3.30pm to 5pm, while the state government activated plans to reduce demand during the peak hours 3pm to 8pm.

This included government agencies reducing demand by increasing the set point of air-conditioning, closing blinds, turning off non-essential lighting and turning off equipment when not in use. It also included invoking an agreement for Water NSW, Sydney Water, Hunter Water, Central Coast Council and the City of Sydney to shift electricity usage to outside peak-demand periods.

NSW Premier Chris Minns said households and businesses could also help reduce demand.

The heat caused Sydney Trains to reduce speeds on the network in parts of the city.Credit: Wolter Peeters

“Wherever possible, wherever it’s safe, consider not using energy-intensive appliances between the hours of 3pm and 8pm this afternoon,” Minns said.

“The reason for that is that solar production in the energy market starts to come off from 3pm at exactly the same time as people return home from work. So if you cannot run your pool filter, not run your dishwasher, not run your washing machine this afternoon between 3pm and 8pm, you’ll help the grid.”

Electricity supply remains tight but the urgent warning issued was downgraded by AEMO by 6pm and the regulator is confident that blackouts will be avoided, barring unforseen events

Climate Change and Energy Minister Penny Sharpe said households could keep cool by closing windows and drawing curtains and blinds and should consider whether air-conditioning needed to be full blast.

Weatherzone.com.au’s forecast maximum temperatures for Wednesday.Credit: Weatherzone.com.au

The hottest place in Sydney on Wednesday was Penrith, which the weather bureau reports as peaking at 39.9 degrees shortly before 3pm, and it was above 38 degrees at Sydney Airport, Sydney Olympic Park, Bankstown, Holsworthy, Horsley Park and Richmond. In the east, Sydney Observatory Hill reached 32.9 degrees about 11am.

The spring heatwave is Sydney’s most severe since November 2020, when the hottest day was 43 degrees at Sydney Airport. It was hot in the Illawarra and Central Coast, but cooler in much of the state.

Globally, 2024 is on track to be the hottest year on record, breaking the previous record set a year ago.

Sharpe said the electricity shortage was caused by ageing coal infrastructure and heatwaves earlier in the year.

Of the four power-generation units offline on Wednesday, two were unscheduled outages and two were planned maintenance to prepare for summer.

“We’ve got coal-fired power, which is still extremely important in NSW and it’s why we have looked at and agreed to the extension of Eraring, but they are also old kit,” Sharpe said. “They’re old plants, and they do have outages – that’s what causes some of the instability that we’ve got.”

Sharpe said coal power had already decreased from 80 per cent of NSW’s power generation to 50 per cent. She said blackout warnings would decrease over the next three to five years as the transition continued because the state was adding new electricity generation from both renewable sources and gas, as well as projects such as the Waratah Super Battery.

Minns added that the energy transition was “not really an ideological question” because ageing coal-fired plants needed to be replaced anyway.

He said the shoulder seasons were when most utilities undertook maintenance and repair to avoid peak demand in summer and winter but climate change meant that “increasingly, you’ll see heatwave conditions earlier and earlier in the year, and, obviously, we have to manage that”.

Stephanie Bashir, chief executive of consultancy Nexa Advisory, said NSW was falling behind in renewable project approvals.

“They wouldn’t be scrabbling now if they were properly enabling consumers to manage their own demand, and unleashing development and connection of renewables, including through orderly closure of coal plants,” Bashir said. “It’s clear that extending Eraring is not even a good Band-Aid.”

AEMO said in a statement it was urging all available generation and powerlines to return to service, and was looking to procure additional reserves and negotiate reduced usage with large power users.

In rare circumstances, if AEMO cannot secure an agreement, it can intervene in the market to cut energy use.

Additional reporting by Anthony Segaert

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