What is Frequency Control Ancillary Services?

Can a wind farm provide important stability services for the Australian power system that are normally the domain of coal-fired or gas power stations? That is the question a new project funded by ARENA seeks to answer.

In an Australian first, ARENA and the Australian Energy Market Operator (AEMO) have signed an agreement with South Australia’s Hornsdale Stage 2 Wind Farm to trial whether a wind farm can provide Frequency Control Ancillary Services (FCAS).

ARENA CEO Ivor Frischknecht said the FCAS trial would test the National Electricity Market’s ability to fully integrate renewables into the electricity system, further assisting Australia’s transition towards renewable energy.

“This is an opportunity for us to enable wind and solar generators to fully participate in the NEM’s energy and FCAS markets by providing frequency control services in addition to generation,” Mr Frischknecht said.

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 AEMO 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.

“The changing generation mix in the NEM is changing the way AEMO operates both the grid and market,” AEMO Chief Executive Audrey Zibelman said. “This trial will enable us to test new and emerging technologies that could supply services the market will need in future.”

Hornsdale Stage 2 is committing $300,000 to the FCAS trial. With that amount to be matched by ARENA, the total funding for the project is $600,000.

Integrating renewables

French renewable energy company Neoen has developed Hornsdale Stage 2 in conjunction with international infrastructure investor, John Laing.

Neoen Australia’s Managing Director, Franck Woitiez said the partnership signalled the shift towards a more sustainable Australia focused on exploring future energy supply services.

“South Australia in particular is leading the charge to secure a more sustainable energy future so we’re proud to be working with ARENA and AEMO on this trial,” he said.

“This project will show the potential of renewable resources like solar and wind power to provide Australia with controllable, clean energy that can keep pace with future demand.”

Pass the remote control

The trial will also demonstrate the technical capability of Type 4 wind turbines to be remotely controlled by AEMO. This will allow AEMO an expanded toolkit to manage smaller deviations in frequency that occur on an ongoing basis.

“AEMO supports and encourages a framework for new technologies that ensures power system security yet continues to encourage competition. This trial is an essential step towards a more efficient and competitive FCAS market that ultimately benefits consumers,” said Ms Zibelman.

Following the successful completion of this capability demonstration, a market trial will run for a minimum of 48 hours to test the ability of HWF2 to fully participate in the NEM and NEM FCAS markets.

This market trial will allow AEMO to assess modifications that may be required to wind forecasting, bidding and energy management systems to support on-going provision of FCAS from wind and solar farms operating in the NEM.

If successful, the trial will provide a critical proof of concept to the market and investors on the ability of wind farms to provide FCAS.

“AEMO welcomes the opportunity to play a role in strategically integrating renewable generation into the National Electricity Market (NEM), to ensure a reliable, secure and resilient power system now, and into the future,” she said.

This article was originally written by Daniel Silkstone, former Head of Content, ARENA.