Victoria power emergency: SA interconnector cut as heat soars

Australia’s power operator called on Victoria to prepare short-term emergency electricity reserves after South Australia was separated from the national grid, cutting a vital source of supply amid sweltering weather conditions.

The Heywood interconnector linking Victoria and South Australia was cut at 1.24pm, according to the Australian Energy Market Operator.

That left South Australia islanded from the rest of the market, triggering a surge in wholesale prices in the state to the $14,700 per megawatt hour market cap.

AEMO then activated the last ditch power mechanism at 1.51pm — known as the Reliability and Emergency Reserve Trader — in a bid to maintain power system security using reserve supplies and demand management contracts previously agreed with the market.

A level two ‘lack of reserve’ was also declared in Victoria on Friday afternoon as a signal for the market to direct urgent electricity supplies to the grid through either a boost in supplies or large industrial businesses cutting demand.

Shortly after the interconnector was cut, Alcoa’s giant Portland smelter was also understood to have been forced offline potentially helping to ease the tight market in Victoria by reducing about 600 megawatts of demand on the system.

South Australia had been exporting about the same level of supply to Victoria at the time of the separation, consultant GlobalRoam tweeted.

“South Australia was exporting to Victoria at the time. The loss of supply almost exactly matched by a 600MW drop in Victoria, presumably Alcoa’s Portland smelter,” GlobalRoam managing director Paul McArdle said.

Portland’s owner, Alcoa, confirmed the outage.

“At approximately 2:20pm on 31 January, Portland Aluminium smelter lost power to both potlines due to a fault external to the plant. The cause of the fault is currently unknown,” an Alcoa spokeswoman told The Australian.

Portland’s owner, Alcoa, was not immediately available to comment.

The market operator boosted its emergency back-up supplies earlier in December across the nation’s power grid to help avoid potential electricity cuts this summer as extreme heat and the ongoing threat of bushfires place the system under pressure.

Victoria, NSW, South Australia and Queensland gained access to 1500 megawatts of RERT power reserves to cover the risk of high temperatures and unplanned generation outages and ensure compulsory load shedding is avoided during periods of peak demand.

Two-thirds of the supply is for Victoria and South Australia and the remainder covering NSW and Queensland to cover risks to the grid.

‘Cut use urgently’

Earlier on Friday Victorians were asked to urgently cut their electricity use this afternoon to ward off potential blackouts, with soaring heat and humidity tipped to push the state’s power demand to a six-year high.

The Australian Energy Market Operator, which runs the national power grid, called for households to reduce their electricity usage between 1pm and 8pm on Friday in a bid to avert forced outages.

Electricity demand is forecast to hit its highest levels since January 2014 due to the combination of heat and humidity.

Consumers have been urged to use air conditioners only at higher temperatures, avoid running dishwashers and switch off pool pumps.

“While AEMO is not currently forecasting supply shortfalls or the need for involuntary load shedding, heatwave conditions that drive high electricity demand, combined with unplanned generation or transmission outages, could result in electricity disruptions,” the operator said in a statement.

AGL Energy’s Loy Yang A coal plant in Victoria’s Latrobe Valley suffered a temporary outage at one of its units just after 6pm on Thursday, piling pressure on the state’s fragile grid at a time of peak demand.

The unit has returned to service but Victoria’s Energy Minister Lily D’Ambrosio said ageing coal plants and stress on transmission lines were partly to blame for the tight situation.

“Today Victoria’s power supply will be very tight due to hot weather. There are many variables that can affect power supply including bushfires, stress on transmission lines and ageing coal plants that can fail with no notice, like we saw last night,” Ms D’Ambrosio said in reference to Loy Yang.

Extra electricity reserves have been contracted by AEMO in an attempt to avoid compulsory cuts.

“AEMO has contracted additional electricity reserves, however, should these be insufficient to manage unexpected outages of generation or electricity transmission assets, load shedding may be required as an absolute last resort to avert the risk of system collapse, physical damage to parts of the power system or long-term outages to residents and businesses,” AEMO said.

Victoria and South Australia both endured a tighter than expected power market on Thursday night as hot weather triggered soaring electricity demand.

The Loy Yang outage, along with the powering down of solar for the night and a low contribution from wind farms meant power supplies struggled to meet demand, according to Paul McArdle at consultancy GlobalRoam.

Demand across the national electricity market at 5pm on Friday is forecast to reach within 500 megawatts of the all-time record, according to Mr McArdle.

While the focus remains on Victoria given a forecast high of 40 degrees in Melbourne on Friday, NSW also faces a tight market with coal units out at AGL’s Bayswater and Liddell plants and EnergyAustralia’s Mt Piper facility in the state, GlobalRoam said.

The heatwave is also expected to move north over the weekend, with central and western NSW surpassing 40C.

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