Can Wind Hybrid Power Plants really provide Ancillary Services?

Antonio Martinez
Director, BoP & SCADA Department APAC at Vestas
Published on 22nd October 2018

Ancillary services are crucial to a grid’s integrity. Frequency control and network support and control are grid services normally provided by conventional coal or gas generation. There’s a misconception that only traditional fossil power stations can provide these ancillary grid services. But now, with the advent of hybrid power plants, this is no longer the case.

And this is good news. With many conventional generation power sources reaching their end of life and being replaced by renewable energy generation, wind hybrid power plants controlled by intelligent, real-time power plant controllers are more than capable of taking on the role of ancillary service providers.

The beauty of a wind, solar and storage hybrid power plant is that, with an integrated power plant controller, it can reliably provide primary, secondary and regulation frequency control services: Lower frequency control is not dependent on wind or solar resources, and the surplus energy required to participate in raise frequency services is now available from battery storage.

Network overload prevention is also possible thanks to the hybrid plant controller and the generator’s fast acting power electronics, which can respond almost instantaneously to a potentially harmful network event: A clear improvement on a traditional plant’s inefficient mechanical systems.

Moreover, hybrid plants are not only able to maintain the steady state voltages required by grid codes, but can also contribute to keeping voltages stable during abnormal network conditions, avoiding blackouts caused by generator outages or network failures.

In effect, a hybrid plant controller uses wind, solar and battery power to emulate a single coordinated generating system to control the network voltage. This provides the same function as a traditional generator’s excitation systems - but more efficiently.

And it’s not even a new product that makes this possible.  The control system readied for Kennedy Energy Park is based on existing, proven technology and is an evolution of what we already use across our fleets. But already, we’re seeing the potential to enhance the controller’s role in maximising our customers’ value of energy via more sophisticated algorithms that enable real-time trading in the energy and ancillary services markets to maximise revenue.