Firm frequency response (FFR)
FFR creates a route to market for providers whose services may otherwise be inaccessible. The FFR service gives us and service providers both a degree of stability against price uncertainty under the mandatory service arrangements.
We have published our findings and guidance on State of Charge Management.
FFR can provide both dynamic and non-dynamic response to changes in frequency:
Dynamic frequency response is a continuously provided service used to manage the normal second-by-second changes on the system.
Non-dynamic frequency response is typically a discrete service triggered at a defined frequency deviation.
There are three response speeds for frequency response.
Providers may offer only one of these or a combination of different response times.
Primary response - Response provided within 10 seconds of an event, which can be sustained for a further 20 seconds.
Secondary response - Response provided within 30 seconds of an event, which can be sustained for a further 30 minutes.
High frequency response - Response provided within 10 seconds of an event, which can be sustained indefinitely.
The FFR service is open to both Balancing Mechanism (BM) and non-BM providers who can meet the technical requirements. This might include generators connected to the transmission and distribution networks, storage providers and aggregated demand side response.
Providers can offer other balancing services outside of their tendered FFR windows.
Units must be ready and in frequency sensitive mode at the start of each FFR window.