What constitutes a reportable disturbance based on NERC DCS criteria for a Balancing Authority with a 900 MW unit?

What constitutes a reportable disturbance based on NERC DCS criteria for a Balancing Authority with a 900 MW unit?

• A. The loss of the 900 MW generating unit at 60% output.
• B. The loss of two 400 MW units 30 seconds apart.
• C. The loss of 750 MW of firm load.
• D. The loss of a 700 MW generating unit at 100% output.

Answer: (B)

A reportable disturbance based on NERC Disturbance Control Standard (DCS) criteria focuses on significant impacts on the reliable operation of the bulk electric system. A critical factor in determining reportability involves the magnitude of the disturbance and any resulting frequency response considerations. The loss of two 400 MW units 30 seconds apart is significant because it represents a total loss of 800 MW in a short time frame, which is more than the capacity of the 900 MW unit. Such an event could lead to stability issues on the grid, especially if the Balancing Authority is not able to quickly balance this loss with generation or other resources. The rapid succession of the unit failures poses additional challenges for frequency control, requiring a response that could involve considerable effort to maintain system reliability. In contrast, the other scenarios, while significant, would not meet the criteria for reportability under the same conditions as a pair of larger losses occurring simultaneously or in close succession. For instance, while losing a generating unit at 60% output or losing a large chunk of firm load has implications, they do not necessarily lead to as drastic a reliability challenge as the dual loss scenario described. Similarly, losing a 700 MW generating unit at 100% output would be significant, but

A reportable disturbance based on NERC Disturbance Control Standard (DCS) criteria focuses on significant impacts on the reliable operation of the bulk electric system. A critical factor in determining reportability involves the magnitude of the disturbance and any resulting frequency response considerations.

The loss of two 400 MW units 30 seconds apart is significant because it represents a total loss of 800 MW in a short time frame, which is more than the capacity of the 900 MW unit. Such an event could lead to stability issues on the grid, especially if the Balancing Authority is not able to quickly balance this loss with generation or other resources. The rapid succession of the unit failures poses additional challenges for frequency control, requiring a response that could involve considerable effort to maintain system reliability.

In contrast, the other scenarios, while significant, would not meet the criteria for reportability under the same conditions as a pair of larger losses occurring simultaneously or in close succession. For instance, while losing a generating unit at 60% output or losing a large chunk of firm load has implications, they do not necessarily lead to as drastic a reliability challenge as the dual loss scenario described. Similarly, losing a 700 MW generating unit at 100% output would be significant, but