Available Transfer Capability (ATC) and Why It Matters

As energy markets evolve and demand for electricity increases, the ability to transfer power reliably across regions is more critical than ever. Available Transfer Capability (ATC) measures how much capacity remains available on the grid for new electricity transfers, after accounting for existing commitments.  

In this blog post, we’ll explain how ATC is calculated, why it’s vital for grid flexibility, and how it impacts energy market transactions. 

What is Available Transfer Capability (ATC)

ATC represents the capacity left on a transmission line after existing power transfers have been accounted for. It’s the measure that grid operators use to ensure that additional electricity can flow without risking grid stability. In short, available transfer capability is like finding extra lanes on a highway — once some lanes are reserved for traffic, ATC tells you how much space remains.

How is Available Transfer Capability calculated?

ATC is derived from Total Transfer Capability (TTC), subtracting any existing reservations or transfers. NERC MOD-30 plays a key role in standardizing these calculations, ensuring grid operators follow consistent methodologies for determining TTC and ATC. This process is critical for grid reliability and market operations.

The Available Transfer Capability calculations take into account factors like: 

1. Existing commitments: Previously scheduled power transfers reduce available capacity
2. System conditions: Factors like weather and maintenance impact available space
3. Regulatory compliance: Operators adhere to standards for available transfer capability definitions and determination, including guidelines from the North American Electric Reliability Corporation.

Why is ATC important for grid flexibility

Maintaining sufficient ATC ensures that the grid can handle new transactions, respond to emergencies, and balance supply and demand. Operators must also ensure compliance with regulatory guidelines from the Federal Energy Regulatory Commission (FERC) to maintain grid reliability and support market transactions. Without enough ATC, grid operators may struggle to manage power flows efficiently, risking potential disruptions.

The role of ATC in the future of grid reliability

As the grid modernizes and renewable energy sources are integrated, managing ATC will become increasingly important. PCI helps transmission operators adjust to these evolving demands, ensuring that power continues to flow safely and efficiently. 

How PCI Energy Solutions helps optimize ATC

PCI Energy Solutions provides tools to help transmission operators optimize available transfer capability in power systems by automating TTC and ATC calculations. These tools ensure compliance with NERC standards, while also helping operators maintain flexibility and reliability across the grid. 

Want to see how PCI supports energy companies in optimizing Available Transfer Capability (ATC) for grid reliability? Explore our transmission and reliability solutions to learn more.