Why do my lights sometimes flicker?

By Chris De Troye, System Engineer

"Did you see the lights flicker?" my wife asks as she walks into the room. By the time she reaches the hallway, I’m already off the couch and putting on my shoes. A flicker can range from a subtle candle-like shimmer to rapid on-and-off switching and can be caused by everyday events such as large appliances turning on to power outages on our system.

What Causes Blinks?

Several things can cause lights to blink. When high-power devices like heat pumps, microwaves, or hairdryers start up, they may cause a brief flicker. Modern lights, especially LEDs, are more sensitive to these fluctuations, particularly as CFL and incandescent bulbs are phased out.

More severe blinks, however, may be caused by a power outage or fault on the power grid. Events like a car crashing into a pole, a tree falling onto power lines, or an animal making contact with electrical facilities can all create faults on the grid. Our protective equipment quickly activates to isolate and address these issues. If a tree branch falls into and then off of the power line, power will typically be automatically restored after a brief blink. If a pole is damaged or wires are down, our linemen will work to resolve the issue.

What Was That Noise?

If you hear a loud "BANG" or a single gunshot-like sound just before the power goes out, it’s likely that a fuse has blown to protect the lines. As we discussed in a previous blog post, while some might say a transformer “blew,” it’s most likely a fuse, similar to those used in electric panels in lots of electronic devices. Fuses blow to prevent damage and stop power flow until the issue is resolved. These fuses typically protect the main lines and automatically isolate faults that occur on smaller segments of the grid that normally serve fewer customers. When a fuse blows, our linemen will check the lines for damage and then make appropriate repairs.

What Should You Do?

If you notice damage, like a downed tree on a power line or broken pole, stay far away. If an electric line is on the ground, there could be power running through it, which can be dangerous. Keep children and pets away from the area and immediately call us to report the damage.

If the power comes back on after a blink, there’s probably no need to call us. We have automated systems that can restore power in less than a minute and automatically notify our dispatch. If the power isn't restored right away, we may already be aware of the issue through our fiber services. However, it’s always a good idea to report the problem to make sure we’re aware. You can call our automated system at 423-968-BTES (2837). In most cases, our system will call you back once the power is restored.

It is important that we have your correct phone number on file. We use this number, tied to your street address, to direct our linemen to the outage. Take a look at your next BTES bill to ensure the phone number we have on record is correct. If it’s not, let us know and we’ll update it for you.