Can this Tassie wind farm provide grid-stability services? We’re going to find out
On the edge of a clifftop in Tasmania’s rugged northwest corner the winds known as the roaring 40s blow regularly and strong.
And the Musselroe Wind Farm is perfectly situated to take advantage. On their own, these 56 turbines provide 5 per cent of Tasmania’s yearly electrical supply.
But, with support from ARENA, this 168 MW power generator is about to take on an even larger responsibility, attempting to answer questions that will be important for our renewable energy future.
Can a wind farm provide the grid-support services needed to ensure stable and reliable supply and which are currently contributed by coal or gas fueled power stations?
And, just as importantly, can they make enough money doing it to make it all worthwhile?
The project, to which ARENA has contributed $497,000 of the $1 million total cost, will use the farm’s wind turbines to supply frequency control ancillary services, known as FCAS.
Woolnorth Wind Farm Holding, which operates the Musselroe wind farm, will provide the remainder of the project budget.
What is FCAS?
The power system requires that both generation and load are in balance in order to operate safely. If there is a variation in generation without a corresponding variation in load then the frequency of the power system will deviate, which can lead to instability or, at extreme levels, cascading failure and blackouts.
FCAS is a process used by the energy market operator to maintain the frequency of the system within the normal operating band around 50 cycles per second.
Put simply, FCAS provides a fast injection of energy, or fast reduction of energy, to manage supply and demand.
Traditionally provided by generators such as coal and gas plants, these services are purchased by the energy market which is operated by the Australian Energy Market Operator to maintain frequency and ensure the stability and reliability of the grid.
This project aims to shake that up, instead using wind power for the same purpose.
So have we tried this before?
In August, ARENA and the Australian Energy Market Operator (AEMO) signed an agreement with South Australia’s Hornsdale Stage 2 Wind Farm to trial whether it could provide FCAS, becoming the first Australian wind farm to attempt to do so.
The Musselroe project will also trial this approach, seeking to discover whether the provision of FCAS services is technically possible, but will add an additional layer of complexity, examining the potential commercial and economic value available to a wind farm from participating in the FCAS market.
It is expected that the provision of these services from wind farms will allow the electricity grid to integrate increasing levels of variable renewable energy while simultaneously improving grid security by broadening the sources from which FCAS can be obtained.
But if renewable sources are to be harnessed as providers of grid support services like frequency control it’s important to know not just that it is technically possible but that sufficient markets are in place to create the incentive for them to do so.
ARENA CEO Ivor Frischknecht said a successful trial at Musselroe could see FCAS be adopted at other Australian wind farms.
“Wind power is playing a big part in Australia’s transition to renewable energy and we want to explore how wind can provide essential grid stability services.
“Musselroe Wind Farm will be able to answer for us the key question that so far hasn’t been answered; does it make economic and commercial sense for a wind farm to provide FCAS and participate in the FCAS markets?” Mr Frischknecht said.
If Woolnorth find that there are real commercial drivers for wind farms, then we should see more and more of them providing FCAS which will lower FCAS prices and in turn lower electricity bills,” she said.
The project also offers several points of difference that make it a valuable complementary addition to the Hornsdale trial
Musselroe runs using Vestas turbines, which differ from the Siemens-built ones at the Hornsdale facility.
Tasmania also offers an environment where FCAS services are required more often, allowing the technical and economic factors at play to be tested more stringently.
The Musselroe site will also examine how a co-located battery storage system can create advantages for how the wind farm can supply frequency control on demand.
General Manager of Woolnorth Wind Farm Holding, Stephen Ross said very few Australian wind farms provide the network support offered by FCAS.
“This project aims to identify the true capability of wind power to provide system support, how that might work and what benefit there would be in terms of reliability and security at local and system level,” Mr Ross said.
“This is an opportunity to prove that wind farms can contribute to the stability and reliability of the electricity network.”