Fast reserve provides rapid and reliable delivery of active power through increasing output from generation or reducing consumption from demand sources.
We use fast reserve, in addition to other energy balancing services, to control frequency changes that might arise from sudden, and sometimes unpredictable, changes in generation or demand.
Who can provide this service
The fast reserve 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.
Providing fast reserve alongside other balancing services
Providers can offer other balancing services outside of their tendered fast reserve windows. However, units must be ready to respond to a fast reserve instruction at the start of each fast reserve window.
When do providers need to be available to deliver this service?
We'll notify successful providers of the times that the service may be required on the 12th business day of each month. These are called the nomination windows.
The fast reserve service is required 24 hours a day, 7 days a week. However, there is a greater requirement for the service during the daytime, typically between 06:00-23:00.
How will providers be dispatched?
The fast reserve service is dispatched electronically. Units providing fast reserve must be ready to receive instructions at the start of each fast reserve window to allow them to be automatically dispatched.
How often will providers be dispatched?
For fast reserve, utilisation can vary depending on system conditions, the demand profile and the generating plant on the system. However on average, providers are utilised for approximately five minutes at a time, ten times a day. The providers are still but are expected to have the capability to sustain reserve for 15 minutes.