The North American Electric Reliability Corporation (NERC) released an industry alert identifying possible discrepancies between the design and the actual field conditions of transmission facilities as a potential reliability issue that needs prompt industry attention. The alert recommends that entities review their current facilities rating methodology to verify that the methodology is based on actual field conditions, rather than solely on design documents, and take corrective action if necessary.

“This is exactly what the NERC organization was created to do — identify possible reliability issues and give the industry the information and opportunity to mitigate those issues before they can cause a major problem,” said Gerry Cauley, president and CEO of NERC.

The alert requires entities to develop a plan to identify and implement any necessary actions to correct their ratings and report that plan to NERC and regional entities by Dec. 15. There are more than 450,000 miles (724,205 km) of transmission lines greater than 100 kV in North America many decades old. It is understandable that there could be discrepancies between design and actual field conditions. Many of these transmission lines are in hard-to-access places. Fortunately, new technologies, such as Light Detection and Ranging (LiDAR) and Power Line Systems-Computer Aided Design and Drafting (PLS-CADD), allow entities to assess their lines more easily.

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