Power use surged and sales of air-conditioners and fans skyrocketed across the Illawarra this week, as scorching temperatures forced hundreds of thousands of people to find ways to stay cool.
Staff at Joyce Mayne Warrawong reported scores of people rushing to buy fans and air-conditioning units on Tuesday, while Harvey Norman white goods staff said they had been "inundated" by customers feeling the heat.
According to data from the Australian Energy Market Operator, electricity demand on Tuesday climbed above 10,000 megawatt hours by 9am and peaked at just under 13,000 megawatts at 4pm.
In comparison, Wednesday's peak was just below 9200 megawatt hours.
Endeavour Energy southern region manager Bill Watts said the Illawarra's power supply had coped well with the increased demand, mainly because many energy-guzzling industries were still on holiday.
Mr Watts said power use peaked on Tuesday at three-quarters of the company's record usage levels, but he predicted it would remain lower until the region experienced two or three consecutive days of hot temperatures.
"Usually on the first day people will just come home from work in the afternoon and switch their air-conditioning on to cool down," he said.
"But once you get a few days in a row, they know it's going to be hot when they come home so will tend to turn their air-conditioning on and just leave it on all day."
To minimise the chance of receiving a high power bill at summer's end, Mr Watts recommended keeping air-conditioning units set at around 23 degrees, shutting blinds or covering windows to stop houses heating up and using fans to move cool air around.
Warrawong electrician Michael Negro has been run off his feet this week, working long outside normal business hours to help residents repair or install air-conditioning.
"All my work has come from these last few very hot days," he said yesterday.
"There's been lots of call-outs for systems that haven't been installed correctly, or systems that are old and have finally died in the heat - plus a fair bit of new work for people who can't stand the heat any more."
If the heat continues, the Infinity Energy Solutions owner expects to have a busy start to 2013.
"We haven't really had a hot summer for about two or three years, so this is the first time it has actually been hot in a while," Mr Negro said.
"And if we have three or four hot days in a row that will get the phone ringing even more.
"I'll have to be up in the roof quite a bit and it will be pretty hot - but I like it."