Available Network Capacity (ANC)

Available Network Capacity, or ANC, is the portion of network capability that remains available for additional connections or transfers after existing uses and commitments are taken into account. It is essentially the remaining headroom between the system's technical limits and the capacity already allocated or reserved.

ANC is useful because it turns a complex set of network studies into an operational planning concept for developers and system operators. Even so, it should not be treated as a permanent or unconditional value, since it can change as projects advance, demand evolves, or network reinforcements are commissioned.

Key Aspects of Available Network Capacity:

• Residual Rather Than Total Capacity: ANC is not the full technical strength of the network. It is the amount left after existing connected users, contractual reservations, and security margins have been accounted for.
• Constraint-Driven Value: The available capacity may be limited by thermal loading, voltage performance, fault level, or stability concerns. The binding constraint can differ by location and by operating scenario.
• Time-Varying Quantity: ANC changes when new projects secure rights, when old reservations expire, when load growth shifts network usage, or when reinforcements increase capability. Published values therefore require regular updating.
• Useful but Not Sufficient Alone: A positive ANC figure is helpful for screening, but it does not replace project-specific interconnection studies. Actual granted capacity can still differ once the detailed connection assessment is done.
• Important for Queue Management: ANC helps operators communicate where headroom exists and where the network is saturated. This can influence project siting decisions and reduce speculative applications in constrained areas.