Fire Risk Mitigation Is a Never-Ending Challenge for Utilities
David Shadle | T&D World
Fire is as old as time, and while we have conquered it in countless ways, it still has a habit of showing up unannounced and unwanted. Nowhere is this more evident than in areas of the Western United States, which see numerous wildfires every year that claim lives and millions of dollars in property. Unfortunately, fires that can be caused by and/or destroy utility infrastructure occur in other parts of the U.S. as well. So, are there tools and practices available to help utilities protect their equipment from wildfires and to help minimize the occurrence of power equipment caused fires?
The answer is definitely yes. In states with hot, dry periods where long expanses of transmission and distribution lines may cross high-fuel environments containing dry grass, brush and forested areas, utilities are increasingly turning to granular herbicides to create vegetation-free zones that act as a fire-break to protect their equipment. According to Paul Escobar with SSI Maxim Company, a reduced vegetation zone creates a defensible space where heat and flame exposure to equipment is reduced. Moreover, granular herbicides can be applied around structures with a broadcast spreader and they protect an area for months. Creating a reduced vegetation zone in the vicinity of distribution equipment like pole mounted transformers or capacitors also helps minimize the creation of a fire should an errant spark occur.
In recent years, utilities across the country have been taking steps to increase reliability and resiliency after a series of major storm events caused major outages. For example, CenterPoint Energy developed a hazard tree inspection program after Hurricane Ike in 2008 to periodically inspect important circuits thought to be potentially at risk due to the presence of certain danger trees including palm and pine species. Unitel implemented a vegetation storm resiliency program (SRP) after experiencing a series of extreme weather events and realizing that standard vegetation management practices may provide insufficient protection from extreme events. The SRP goes beyond the company’s traditional core vegetation management program consisting of cyclical pruning and hazard tree removal by conducting detailed tree risk assessment on critical circuits to remove all failure risks and ensure ground-to-sky clearance. Not surprisingly, the storm hardening practices conducted by both utilities also serve to help minimize the risk of fires resulting from vegetation caused equipment damage…(Read the full story)