How often is the Available Transmission Capacity (ATC) calculated for the next 31 days?

The Available Transmission Capacity (ATC) is typically calculated every 24 hours for operational planning over the next 31 days. This regular calculation helps ensure that transmission operators can effectively manage the flow of electricity across the grid, accommodating changes in demand, generation, and transmission constraints.

By updating the ATC daily, operators can respond promptly to any changes in system conditions and effectively plan for future utilizations. Calculating ATC more frequently, such as every hour or every 12 hours, may not be necessary for long-term forecasts beyond 31 days, as the key factors influencing capacity can remain relatively stable in that time frame. Thus, a 24-hour cycle offers a balance between timely updates and the workload involved in recalculating these capacities.