The Australian Energy Market Operator says it is confident that adjustments made to wind farm software means there is no risk of the South Australia blackout being repeated in the future.
AEMO chairman Tony Marxsen told more than 100 energy experts at a presentation under the auspices of the Electrical Energy Society of Australia last week that the “system black” event in South Australia in September – which has set off a huge debate about renewable energy across the country – would not be repeated.
According to several people who attended the talk, Marxsen said AEMO had analysed the failures that contributed to the blackout, and their possible remedies, such as making power poles more resistant to strong winds and better demand response programs.
So far, he said, only one remedy had been implemented – adjusting the ride-through settings on the wind farms in the state. Extensive AEMO modelling, Marxsen told the audience, showed that this would be enough to prevent a repeat of the “system black” event that put the whole state in darkness for several hours.
“If the same sequence of events happened today the system black would not occur,” Marxsen told the audience, according to one source.
This is an important concession from AEMO. It suggests that South Australia, even with around 40 per cent wind energy and a further 6 per cent from rooftop solar, is not at risk of a system-wide shut-down that affected the state late last year.
Of course, there is little the AEMO can do to prevent isolated blackouts, such as the storm-related events that affected more than 100,000 customers in Western Australia last year, and blackouts in Queensland, where there is no large-scale renewables.
In its reports after the blackout, AEMO said it was not the nature of wind energy (i.e. its variability) that contributed to the blackout, but the ride through settings on the wind farms.
Apparently unbeknown to AEMO, many wind farms had ride through settings that forced the turbines to shut down as a self-protection mechanism after a handful of major faults or voltage changes in a short period of time.
This issue was identified and addressed a decade ago in Europe, where no blackouts have been reported despite the high reliance on wind energy in some countries. There is some controversy about AEMO’s claims that it could not have known about the nature of those settings.
Indeed, Marxsen told the audience that in the age of the internet software changes could be downloaded by the manufacturers without the market operator knowing. He likened it to an update of an Apple iPhone, where the user has no idea what is being changed.
This, he made pains to point out, wasn’t an attack on wind, but a recognition that we are in a new world, so we need new ways of dealing with that.
Indeed, culture as well as technology will be critical components of managing the grid in the future. If power engineers, like many in the mainstream media, refuse to believe that wind and solar can play a dominant role in the grid, then the task will be difficult.
But that cultural change is likely to come soon, with AEMO’s appointment of a new CEO, Audrey Zibelman, who has been running the state of New York’s ambitious Reforming the Energy Vision program, which looks to a renewables-based distributed grid in response to the blackouts caused by Hurricane Sandy.
New York intends to reach 50 per cent renewable energy by 2030 – a target proposed for Australia by Labor that has caused so much controversy in political circles and the mainstream media.
But it is not just Zibelman pushing this line. Chief scientist Alan Finkel, in his draft report prompted by the SA blackout, said while there were challenges to incorporating high levels of variable renewables, there were ready technology solutions.
He also pointed out that the wind farm settings had been identified and solved in Europe a decade ago.
This view was echoed and re-inforced by a report from the CSIRO and Energy Networks Australia, which represents the nation’s grid owners, which said that Australia could, and should, aim for high levels of renewable energy – both for climate and environmental reasons and because it was cheaper.
It also envisioned a grid in South Australia with more than 80 per cent renewables, a level the state appears to be heading to given the number of proposed and confirmed renewable energy projects.
AEMO is not due to release its final report into the blackout until March. After that, it will be the turn of the Australian Energy Regulator to investigate AEMO’s actions.
The AER report will likely focus on two contentious aspects. One is the AEMO’s lack of knowledge about the fault ride-through mechanisms, another is its decision to take no action as the storms approached South Australia and swept across the state with increased ferocity.
Marxsen again defended AEMO’s actions at last week’s presentation, saying there had been no forecast for the tornadoes that tore down three main transmission lines that set off the sequence of events that caused the system black.
But energy experts also note that since that time – and previously – AEMO has been taking a much more cautious approach, announcing contingency measures in Queensland during recent summer storms.
There is a large body of experts that say AEMO could, and should, have taken a series of measures such as putting more gas plant on standby, or reducing the reliance on the interconnector to Victoria.
Marxsen, however, told the ESAA audience last week that there was no evidence that having more thermal capacity (coal or gas plants) could have avoided the sequence of events, given the amount of wind capacity that was lost when the fault ride through mechanisms were triggered.
