The energy market operator says households in Victoria and South Australia are unlikely to suffer unplanned blackouts today, despite extreme temperatures across both states putting the power system into a "very tight situation" to keep up with demand.
Temperatures are expected to soar well into the 40s in both states today and tomorrow. In Adelaide, the mercury could exceed its all-time record of 46.1 degrees Celsius today. A top of 49C has been forecast for Port Augusta and 47C for Port Pirie.
Maximums in the 40s are forecast for most of Victoria today, and it is expected to be even hotter on Friday, when temperatures are tipped to reach 43C in Melbourne and 46C in Mildura and Swan Hill, in the state's north-west.
The Australian Energy Market Operator (AEMO) has forecast the possibility of a power supply shortfall in both states tonight if the market is unable to provide additional energy.
The operator has also forecast a tightening of electricity supply reserves in both Victoria and South Australia for several hours today and in Victoria for much of Friday, which would prompt it to seek additional power to prevent blackouts.
Not a good time to do the washing
But AEMO's chief executive officer, Audrey Zibelman, said based on the agency's predictions this morning, there should be enough reserve power to cater to consumer demand without the need for load-shedding blackouts.
Load-shedding blackouts happen when power companies start switching off their customers' power supply because the system is at risk.
"What we always do is we like to make sure that we have enough generators in reserve so that if we were to lose a generator we could replace it with something else," Ms Zibelman told ABC Radio Melbourne.
"If we lose another unit, then we will have to dip into the reserves that we have available to replace those units."
"The way it works is that obviously we first go to the generators that are there in the market, then we go into our reserves … and then, only then, would we ask for people to reduce their usage.
"But that's the last point, and we're not even close to that yet."
Ms Zibelman also called on consumers to do their part to reduce demand across the network, particularly between 4:00pm and 7:00pm when demand is highest.
"We're asking folks to be conscious of not using appliances like washing machines and dishwashers that they don't have to use," she said.
"Think about putting your thermostat up at 24C, not freezing the house out. Doing things to make yourself comfortable and safe … but at the same time be aware that if you don't have to use it, don't."
Three power units are currently offline across Victoria, including two units at Yallourn Power Station and one at AGL's Loy Yang Power Station.
But what happens if reserves are not enough?
If a supply shortfall were to eventuate, it could result in load-shedding blackouts in both states.
To prevent blackouts, AEMO sources emergency energy reserves that are typically not available to the market and are only accessed when supply is not keeping up with demand.
Those emergency reserves — otherwise known as Reliability and Emergency Reserve Trader (RERT) resources — cost taxpayers in Victoria and South Australia almost $52 million last summer, according to AEMO, adding an average of $6 to each household bill.
AEMO can also take action to manage demand — for example, by paying heavy energy users such as smelters to power down during hours of peak demand.
Ms Zibelman said AEMO did not expect it would need to ask smelters to close in order to cope with the current situation.
SA Premier says state 'should get through'
South Australia's Energy Minister Dan van Holst Pellekaan said yesterday based on predictions from AEMO, South Australians should be protected today.
"At this point in time, based on the AEMO's predictions, we expect that while it may be difficult, we should get through," he said.
"There is another 240 megawatts in addition, so in terms of complete resources available to AEMO and to South Australians, we have 17 per cent additional reserve, over and above the peak demand predicted at the moment.
"That's tighter than we'd like it to be but at this point in time, it's very manageable. We look at this every half hour, 24 hours a day in times like this."
Releasing its summer outlook last November, AEMO warned of a heightened risk of forced blackouts in both Victoria and South Australia, partly due to Bureau of Meteorology forecasts of drier conditions, warmer than average temperatures and extended heatwaves.
But it noted that as much as 2,100MW of new energy generation and storage capacity — mainly from wind and solar generation — would be added to the grid in time for the summer.
The SA Government last year introduced grants of up to $6,000 for household battery systems, which it hopes will help shore up the power grid while bringing down household bills.
In Victoria, the Andrews Government has promised to provide half-price solar batteries for 10,000 homes.ABC