Mandatory frequency response (MFR)
Mandatory frequency response (MFR) is an automatic change in active power output in response to a frequency change. The service helps us to keep frequency within statutory and operational limits.
The service is mandatory for large generators and so there is no tender process.
Mandatory Service Agreement (MSA)
The Mandatory Service Agreement (MSA) allows us to instruct the service as required.
When a generating unit is built or modified, we must test its capability to provide MFR. Once the generator has successfully met the minimum requirements, an MSA can be put in place, or amended if a unit has been modified.