26 July 2021
It has been a week of records. Just five days ago, the most that Australia’s growing fleet of wind turbines had produced at any one time stood at 5,642MW, a level set in May. By the end of Sunday, that record had been comprehensively smashed a number of times, and now stands nearly 800MW higher at 6,428MW.
Did Australia suddenly install hundreds of new turbines that were switched on in the last week? Not really – some big wind farms did start production, including the country’s biggest at Stockyard Hill, but are still only operating at a fraction of their rated capacity as they go through commissioning.
The biggest contribution – apart from it being a windy weekend – came from a leap in output from South Australia, where there has been no new wind capacity added for a while, but where artificial caps on their output were significantly relaxed.
Trials have begun for the first synchronous condensers to be installed in the South Australian grid. All four – two at the Davenport substation near Port Augusta and two at the Robertstown substation – are expected to begin commercial operations by the end of this month or early August.
These are not exciting technologies – they’ve been used for the past half century or more to fix problems and weaknesses in various parts of the grid, and were thought to have seen their heyday, if they ever really had one.
But the ability of these big spinning machines to provide synchronous generation without actually burning any fuel is proving particularly useful in some parts of the grid, and could be a game changer in South Australia.
This state already leads the world with the share of generation from “variable” renewables, wind and solar, which has averaged just over 60 per cent in the last year.
But it could be so much more – the state has around 2,000MW of wind capacity, and another 330MW of large scale solar (along with 1.6GW of rooftop solar).
But the large scale wind and solar farms have had their combined output capped at less than 1300MW for much of the time (and an absolute cap of 1700MW) because of the need to have a certain amount of “synchronous” generation to keep the grid secure.
That has meant gas turbines have had to be called into service even when they were not needed for their energy. Such directions have been issued hundreds of times in the last two years, at an aggregate cost of tens of millions of dollars.
But the commissioning of the new syncons will change that, and will likely lead to a significant boost in the share of wind and solar in South Australia, and help set new wind output records in the national grid as it has done in the last five days.
Now, in an update quietly published a week ago, it has revealed that the addition of all four new syncons – now expected in the next week – will allow that combined capacity to produce at up to 2,500MW.
These new combinations and limits will only be applied once all four synchronous condensers – built by global energy heavyweights GE and Siemens – have been tested and operated for up to four weeks without any issues.
Reliability testing at Davenport is well advanced and they are expected to be in operation by the end of the month, but Covid and weather delays have affected Robertstown, so those two syncons may not be available until early August.
The important thing to note here is that under the new guidelines wind and solar will be able to reach these levels with only two other gas generators in operation. Previously, it has required around six or more gas generators to operate to even allow wind and solar to reach the 1700MW cap.
These revised limits will accommodate not just peak production from the current fleet, but the addition of more capacity as the Lincoln Gap wind farm is doubled to around 464MW, and Australia’s biggest hybrid wind and solar facility, the 317MW Port Augusta Renewable Energy Hub, is also switched on.
The next big event in the rapid transition of South Australia’s grid towards the state Liberal government’s target of “net 100 per cent renewables” will be the construction of the new transmission link to NSW, the $2.3 billion Project EnergyConnect.
This which will trigger another major round of renewable energy investment – in both South Australia and NSW – before and after it is opened in late 2024/25.
Already, massive new projects such as Neoen’s Goyder South and its Crystal Brook projects – both combining huge amounts of wind, solar and storage – and Transgrid’s offshoot which is looking at 2.5GW of wind, solar and storage at both ends of the interconnector, but mostly in NSW.
By that time it may be that AEMO and grid owners have become comfortable with battery storage technologies operating in “virtual machine mode”, which allows them to do what syncons do, at a fraction of the cost. The new heyday for syncons may not last long.
And the next step, towards the government’s new target of multiple levels of renewable generation – to satisfy the growing markets for renewable hydrogen and ammonia – will be bringing down the cost of electrolysers.
See also RenewEconomy’s renewable energy maps: