One of the country’s biggest and most recent wind farms will conduct a major trail in South Australia in June to try to dispel one of the biggest myths about wind energy – that wind farms are unable to add to energy security.
The trial – involving the newly constructed 100MW Hornsdale 2 wind farm (which will only be beginning production this week) is being funded by the Australian Renewable Energy Agency and will also involve the Australian Energy Market Operator.
The intention is to show that wind farms can provide what is known as FCAS – frequency control and ancillary services – a critical component in ensuring grid stability in the face of unexpected voltage swings and other faults. Many insist that only coal and gas generators can provide this so-called “inertia” to the grid.
AEMO believes that encouraging wind farms to provide FCAS will add more fuel choice to the narrow FCAS market, and lower prices. Currently, only a few gas generators provide FCAS in South Australia, leading to massive price spikes when the service is called upon.
The program is part of a new, and many would say belated, push to focus on energy security as South Australia heads towards a 50 per cent share of its energy output from wind and solar, a level it is likely to reach this year as the three stages of Hornsdale are complete and the state’s new solar farms are being built.
ARENA this week is also expected to announce a full feasibility study into a potential 200MW pumped hydro facility on the Eyre Peninsula in South Australia.
As for wind-provided FCAS, some grid operators around the world, such as in Quebec, have required wind farms to provide FCAS for more than a decade. This has been followed by Ontario and is now being adopted in European grids.
In Quebec, which has more than 3,000MW of wind generation, more than two-thirds of its wind capacity can now provide what is known as “synthetic inertia”, which can respond to voltage changes of the type that helped bring down the South Australian grid last September.
That and subsequent blackouts, although not the fault of renewable energy, have sparked a fierce backlash against renewables by the Coalition, the right-wing commentariat and, of course, the coal industry.
However, the trial in June, which will run for 48 hours, is designed to show that wind farms can provide those services as efficiently as the gas generators currently in the market.
Hornsdale is being built after winning contracts with the ACT government auction program that has underpinned its plans to source 100 per cent of its electricity needs from renewable energy by 2020.
By the time Hornsdale 3 is completed in July, the wind farm will boast 99 Siemens 3.2MW turbines, or a total of 309MW.
“The importance of this test is that if it works as expected that is very good news for the integration of more renewable energy in the grid,” says Franck Woitiez, from the French company Neoen, which owns the Hornsdale complex,
“Traditionally, FCAS has been provided only by fossil fuel generators – gas and coal. This will show that wind can provide the same stability services as baseload, and that its contribution is broader than just providing sustainable and cheaper electricity.”
One of the problems with the FCAS market is that it has been dominated by gas generators because there has been little incentive for wind farms to contribute. But a redesign of the rule is likely to address those issues and encourage more wind farms to provide that service.
“Frequency on the electrical system …. has traditionally only been provided from synchronous thermal generation,” federal energy minister Josh Frydenberg said in a statement.
“This builds on steps already taken to stabilise the grid following the September 2016 blackout in South Australia, which includes a new requirement for two gas generating units to be on at all times, a greater constraint on the Heywood interconnector and more robust settings on wind farms.”
That last point refers to the “ride through mechanisms” that forced nine wind farms to stop producing after multiple voltage swings resulted from tornadoes tearing down three major transmission lines. Those settings – unknown to the market operator although identified as an issue in Europe more than a decade ago – have now been corrected.
Frydenberg said the government had also asked the Bureau of Meteorology to “embed its expertise” within AEMO as an immediate step to strengthen their forecasting capability.
This followed the forced rolling outages in South Australia earlier this month, when the market operator botched its temperature and wind forecasts and found itself without enough power to meet supply, even though one major gas generator was sitting idle.
The situation was worsened because several gas plants failed at the last moment because they were unable to deal with the high temperatures.
Since last September’s blackout, many journalists – particularly those in the Murdoch media and the ABC – have written that renewables cannot provide inertia and other services such as primary and secondary frequency response.
The US government’s National Renewable Energy Laboratory wrote last year that this is not true. “Studies and recent operational experience have found that when providing active power control, wind and solar can provide a very large fraction of a system’s energy without a reduction in reliability.”
“In fact, most wind and solar farms can do much more than just stick around during trouble,” the NREL wrote.
“For example, most utility-scale installations—and even some residential rooftop solar systems—are designed to combat voltage sags on power grids. Their electronic inverters can detect brownouts and generate reactive power (AC whose current wave leads its voltage wave) to raise the grid voltage.”
Another report in IEEE Spectrum explains how this happens:
“To emulate the inertial behavior of massive rotating equipment, a renewable generator must somehow find extra power quick.
“Québec’s wind turbines do so through a collaboration between the turbines’ solid-state power electronics and their moving parts.
“When the wind turbines see an imbalance between load and generation that causes a frequency deviation on the system they’re able to … extract some kinetic energy that is stored in the rotating masses of the wind turbines.”
Now, finally, these capabilities are about to be used in Australia.