Power lines are a ubiquitous part of the national landscape, from high voltage transmission lines (500kv) on high arching towers to low voltage distribution lines (7-13kv) that line our city streets. As unsightly as they are, we take them for granted because they deliver the energy that makes modern life possible. The only time power lines pose an immediate danger to people and property below is when they fall.
Power lines are built to withstand high winds, but projectiles commonly associated with extreme high wind events, including tree branches and debris, can snap a power line in an instant. Compromised power poles, caused by vehicle collisions or impact by falling trees, can quickly bring one or more lines down.
For years, public utilities have been working to minimize the impacts of downed power lines, but traditional sensing methods relying on a dramatic change in voltage transmission often don’t detect a downed power line until it is too late – this is because ground contacts conduct energy from the fallen line to keep the power flowing at a rate that doesn’t trip sensing equipment.
Falling Conductor Protection (FCP) technology is being developed and deployed in Western States to mitigate wildfire ignition by downed power lines. Tests have been very successful, and usage is rolling out to wider geographic areas, primarily addressing wildfire season in affected regions. Meanwhile, recent years have seen basically every state in the nation, including Hawaii, withstand increasingly severe storm events. For these reasons, public utilities coast to coast should consider deploying PLTE private networks that can enable FCP technology,
A recent report in the Washington Post revealed that our traditional understanding of the nation’s hurricane region is going to dramatically change, “1 in 3 Americans may face risk by mid-century as winds are projected to reach further inland, northward.” Beyond the Gulf region (Texas, Louisiana, and the Florida Panhandle), and the East Coast (including Florida, the Carolinas, New England), cities as far inland as Jackson, Mississippi, Birmingham, Alabama, and Atlanta, Georgia could soon experience hurricane force wind events. Meanwhile states as far north as Illinois, Kentucky, and Tennessee may see gale-force winds. Atmospheric River events have deluged California and driven severe weather systems across the Midwest, ending up with high intensity storms all the way up into Maine. Moisture associated with these storms widens the immediate threat area of a downed power line well beyond the 35 feet one is recommended to stay away until rescue crews arrive. Meanwhile, tornado activity is up nationwide from the Deep South through the Midwest. In early 2023, a firefighter in Michigan was killed by a downed power line.
For utilities unfamiliar with how FCP works, here’s a primer in more layman’s terms. For a deeper understanding of the technology, Schweitzer Engineering Laboratories (SEL) offers a series of detailed white papers. When a power line breaks free of the pole, considering an average height of 25 feet, it takes about 1.25 seconds for it to hit the ground. FCP detection equipment on each side of the monitored line checks the line 30-60 times per second, relaying data packs to a centralized command, where an algorithm checks for abnormalities. Should a red flag be detected, central command can return a signal to the affected area and cut off power to the affected line – all within milliseconds. For this technology to work, it is essential that the data packets are sent and received to the fastest degree possible, without compromise.
It takes a large team to develop, test, and deploy this technology with partners. On many high profile projects, SEL has been at the forefront of innovation in terms of software and hardware engineering, with SAC Wireless playing a vital role in deploying the private long-term evolution network technology (PLTE) that leverages a variety of applicable bands, including 3.5 GHz CBRS and Anterix 900mhz spectrum. Low latency, highly available (HA) and highly reliable (HR) private network technology prevents data transmission from slowing during peak usage windows experienced by public networks on open spectrum. FCP “synchrophasors” – described by SEL as “high-speed measurements of phase angles, voltages, and currents that are time-stamped, or synchronized” – can be prioritized for transmission through the PLTE to ensure successful 2-way communication between the line and command center, thousands of times every minute of every day, in all weather conditions.
FCP helps utilities keep the power on when end users need it most. By increasing the chances of killing power to a single line in a split second, the utility may not need to darken entire regions during a storm out of an abundance of caution. This strategy can save backup power generation at hospitals and other vital services for extreme events only.
FCP is only one of many benefits PLTE technology brings to public utilities and the communities they serve. Grid modernization (making it more efficient to bring wind and solar energy onto the grid), advanced metering, network security (both from cyberattacks and substation vandalism), and network consolidation are other reasons the time is now to invest in utility communication network upgrades. But as our nation’s weather patterns get more and more extreme in the years to come, FCP makes such investments most urgent to best protect people and property nationwide.