Brown coal generators rated least reliable in the country: report

Loy Yang power station AGL shareholder resolution
AGL’s Loy Yang A power station.

New analysis compiled by The Australia Institute has found that Victoria is over-represented when it comes to generator faults; Victoria is home to 20% of the NEM’s coal and gas generation capacity, but is the source of 35% of all power station outages.

The worst culprits are Victoria’s three remaining brown coal generators with, Loy Yang A and Yallourn power stations rated the worst in the country.

The report raises further questions about the reliability of some of Australia’s largest fossil-fuel power stations, undermining the arguments of coal advocates who say that coal generation is necessary for a reliable grid.

“Victoria’s coal power plants are responsible for the highest number of breakdowns in the country, putting the state’s electricity supply at serious risk,” director of The Australia Institute climate & energy program Richie Merzian said.

“It’s worrying that Victoria’s heavy-polluting coal plants already struggle to consistently supply the state and climate change will only increase the difficulty with more days of extreme heat and higher demand.”

“Across the national grid, Victoria’s aging coal-fired power stations are the most likely to fail and Victorian’s felt this first-hand in January this year when many were forced into blackout.”

Loy Yang and Yallourn W topped the list of outages since The Australia Institute started the ‘Gas & Coal Watch’ project in December 2017. Out of a total of 185 outages observed since the project commenced, 29 outages have occurred at Loy Yang A, and an additional 26 outages occurred at Yallourn W.

Source: The Australia Institute
Source: The Australia Institute

Even after accounting for the size of the power stations, the brown-coal generators still performed poorly, with Yallourn W rating the worst with 17.9 breakdowns per GW, and Loy Yang A rating third, behind Tallawarra, with 13.1 breakdowns per GW.

AGL was recently forced to reveal that an extended outage at the Loy Yang A power station was going to have a material impact on the companies profits. Telling the ASX in a statement that the estimated impact would be a reduction to underlying profits of between $60 to $100 million. The generator has been out of action since 18 May, and is not expected to be back online until the end of the year.

Source: The Australia Institute

The outage of Loy Yang A’s Unit 2, which has taken 530MW of generation capacity offline, is the tenth in a series of outages since December 2017, the worst record of all generator units in the NEM.

“It is unsurprising Loy Yang A has taken Unit 2 offline for over half a year given it is the least reliable unit in the entire national grid and other Victorian coal plant units aren’t far behind.” Merzian said.

Generators were particularly fickle during times of high temperatures, with The Australia Institute analysis finding that power stations had at times gone offline at the worst possible moments.

“On the 25th of January, large scale solar farms were running at 93 per cent of their maximum output, which is in stark contrast to Victoria’s brown coal generators, where 1,600 MW of generation was offline,” the report said.

“Solar power has consistently stepped up as gas and coal plants failed. While coal becomes less reliable in the heat, on hot days Australians can count on solar power for a consistent supply of electricity.” Merzian added.

“It’s time for Victoria to expedite the transition to clean energy and that means shutting down its brown coal-fired power stations over the next decade.”

Michael Mazengarb is a Sydney-based reporter with RenewEconomy, writing on climate change, clean energy, electric vehicles and politics. Before joining RenewEconomy, Michael worked in climate and energy policy for more than a decade.

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