Generating plant frequency control services

During pre-vesting negotiations to establish the England and Wales electricity Pool (prior to March 1990), it was agreed that the quality of electricity supply should be managed by the separate procurement and despatch of technical services. An ancillary services business (ASB), was set up as a licence business of the National Grid Company (NGC) and was bound by an economic purchase obligation to arrange a portfolio of contracts for voltage, frequency, reserve, transmission constraints and grid recovery services. The structure of and the strategy behind the contracts enable the grid operator to utilise them as necessary to facilitate reliable and economic system operation in the energy market. This paper addresses some key aspects of the measures taken to identify the requirements for, and register the capabilities of, generating plant to provide automatic frequency control as a service.