Connection and Use of System Code (CUSC), constitutes the contractual framework for connection to, and use of, National Grid’s high voltage transmission system.

• CUSC Summary
• CUSC Code

At privatisation and as required by the transmission licence, National Grid implemented the Grid Code, which is designed to permit the development, maintenance and operation of an efficient, co-ordinated and economical system for the transmission of electricity, to facilitate competition in the generation and supply of electricity and to promote the security and efficiency of the power system as a whole. National Grid and users of its transmission system are required to comply with the Grid Code.

• Grid Code

This code was activated on the BETTA Go-Active Date (1st September 2004). The STC Code defines the high-level relationship between the GB System Operator and the Transmission Owners. It is supported by a number of procedures (SOTO Code Procedures or STCPs) that will set out in greater detail the roles, responsibilities, obligations and rights etc of the GBSO and the TOs.

• STC Summary
• STC Code