Dynamic line rating is becoming one of the most important functions of a utility operations in many regions. The ability to maximize loads during varying environmental conditions while maintaining ground clearance, equipment integrity and safety is critical. It allows the utility utility to maximize the aging grid, improve efficiency and reduce costs and help avoid power outages. One of the biggest challenges to line rating is extreme temperatures. Extreme heat can lower the ability to transmit power, however during that time, consumer use may rise due to an increased usage of air conditioning. Increased usage by consumers can overtax the grid, and in some cases, cause a power outage or force managed rolling blackouts.
Extreme temperatures can also affect the overall ‘health’ of a utility line. High temperatures can shorten the life of components, but also cause abrupt failures. By far the most critical result of extreme temperatures is line sagging which can result in flashover events, or direct contact with nearby vegetation, both contributing factor in wildfire growth, threatening large utility areas. On the other extreme, freezing temperatures after heavy wet snow, prolonged frost accumulation and ice build-up can increase the snapping of damaged power line cables, transformers or support structures. Combined with high winds, roping can occur which may result in faults, downed lines, possible equipment damage or power outages.
