Transmission Constraint Management


National Grid procures Balancing Services in order to balance electricity supply and demand and ensure the security and quality of electrical supply across the GB Transmission system in an economic and efficient manner. There are two types of balancing actions. Energy imbalance actions adress overall mis-matches between generation and demand at a national level. System imbalance actions tackle local or regional constraints in the capacity of the transmission network. Transmission Constraint Management is one type of system Balancing Service.

Constraint management is required where the electricity transmission system is unable to transmit the power supplied to the location of demand due to congestion at one or more parts of the transmission network. In the event that the system is unable to flow electricity in the way required, National Grid will take actions in the market to increase and decrease the amount of electricity at different locations on the network.

One action that National Grid can take is to enter into contracts to agree output with a service provider ahead of time to aid the management of a transmission constraint.