A lineworker's timeline: Restoring a power outage
“How long is it going to take?” These are familiar words to all who work in the electric industry. It’s a phrase our lineworkers have been asked thousands of times. By phone, through car windows, from front porches, sidewalks, bicycles, gas pumps, and diners. It’s the first thing people think when the lights go out. It doesn’t take long sitting in the dark to realize how dependent we are on electricity. How much it makes our lives better and easier.
But what does it take to get those lights back on? Why does it sometimes take so long? Most people will never get to experience or witness the work that goes into ending outages. Hopefully, after reading this, you will better understand the process and the work that Cass County Electric Cooperative line crews are doing to restore your power.
The electricity you use travels a great distance and goes through several steps to get to your home. It starts with a power plant. Power plants use fuel to produce power. That fuel could be coal, hydro, wind, or solar. A power plant typically produces voltages of less than 30,000 volts. That voltage needs to be “stepped up” so it can travel long distances. That process starts next door in the power plant’s substation and switchyard. In the substation, a transformer will step the voltage up to 345,000 volts, or sometimes higher, and send it out on transmission lines to another substation.
At the next substation, electricity starts to get closer to its destination. Here, we start stepping the voltage down. A transformer will step the voltage down to 69,000 or 115,000 volts in this second substation and send it out to smaller local substations.
These local substations are the final substation before the electricity reaches your home. Here, it is stepped down, again with a transformer, to the 7,200 or 13,800 volts that can then be delivered to the equipment outside your home. Once it arrives outside your home, it is stepped down a final time, yes, by another transformer. This final transformer will step the voltage down to 120/240 volts that operate all the devices that power your life.
What was just described is hundreds of miles of line and thousands of poles. That’s a lot of exposure for something to happen and cause an outage. Just like your home, our system has breakers. Our breakers help us reduce the exposure of the line and allow us to split our system into sections. Doing so helps limit the size of the outages and allows us to keep as many people on as possible. Breakers also help to protect equipment on the line. Ever wonder why your lights blink a few times before going off? That’s the breaker. They operate a few times, trying to give the fault a chance to clear the line before they open for good.
Now that the lights have blinked, your breaker has opened, and the power is off. So, what happens?
The outage begins:
6:35 p.m.: Your local lineworker gets a phone call.
When an outage occurs, the first question is, “Is this an individual or a line outage?” A line outage will be a large section of line and several people. An individual could be just a single transformer or pole. If it’s a line outage, the next question is, “What’s the first upline device?” This is why it’s important to report your outage. Based on the outage calls, the software CCEC uses will predict the most likely protective device that operated.
Heading toward the outage:
7:00 p.m. The drive.
An after-hours outage requires your lineworker to respond from home. CCEC lineworkers must live within 30 minutes from the service center they work out of and must drive to the shop first to get their truck and the proper equipment. Depending on where the outage is, the drive alone can sometimes take an hour.
7:45 p.m.: Arrival and line inspection.
During an outage, you may see a lineworker drive past several times. The first time you see them, they are most likely driving to the breaker to verify that it’s open. The second time you see them, they are visually checking the line for what may have caused the outage. Checking the line is one of the more time-consuming steps but is also one of the most important parts of restoring an outage. Re-energizing the line without checking for damaged equipment or fallen lines would be very dangerous to the public. This could cause more damage and extend the outage longer.
Another factor that can add time to inspecting the line is terrain. Electric co-op lines go where needed, which might be in remote or hard-to-access places. The terrain and direction of the line sometimes require us to run the line offroad. The line must be checked on foot if it’s not along the road. If it’s dark, this job can be even more time-consuming.
The process of repairs
8:30 p.m.: Outage cause located, but first, safety.
Once the cause of the outage is found, safety steps must be taken before starting the work. These safety procedures add time, but they are vital. It’s how our lineworkers survive a dangerous job and ensure everyone goes home to their families. The most important thing they must do is isolate and ground the line. This protects back feed from home generators. Your home generator, if installed wrong, could back feed through your transformer and put primary voltage back on the line. Lineworkers install grounds as close to the work location as they can on both sides. These grounds connect the neutral wire to all primary wires, making them all the same ‘grounded potential’ and safe to work on. The final safety step is the briefing, where the job plan is discussed and explained, hazards are identified, and everyone is made aware of the grounds, their location, and the location of the breaker.
9:00 p.m.: All safety procedures are in place. We can begin work.
Let’s say that for this outage, it was a tree. A 50-foot-tall oak tree fell through the line. It’s off the road, but our lineworkers got lucky—it broke a crossarm, but the pole is good. The wire isn’t broken either but is currently under the oak tree. They must chop the tree and free the wire. This will take some time. They must be careful and pay attention to the tree and how it’s sitting on the ground. Downed trees can shift and roll while being cut. And here, you also have power lines under tension, pinned down by the tree, adding an extra layer of danger. Sometimes, the power lines must be tied down so that they can be let up in a more controlled manner once the tree is cut. While they work to clear the tree from the line, new material is on the way.
10:30 p.m.: The tree has been cleared, and the material has arrived.
If a bucket truck can’t reach the pole, a lineworker must climb it. One of our lineworkers will put on his belt and hooks and climb to the top of the pole, bringing all the tools he’ll need with him. One thing he will take with him is a handline. This is a rope in a pulley that will be used to lift material and other objects to the lineworker that are too heavy or awkward to take up in his belt. Once he gets to the top of the pole, he will remove all the broken material and inspect the top of the pole for damage they couldn’t see from the ground. Once it’s cleaned up, the other lineworkers will start sending up material on the handline. The lineworker on the pole should have taken the crossarm bolt with him and installed that in the pole. The lineworker on the ground will tie the crossarm with everything on it onto the handline to allow the lineworker on the pole to guide the arm onto the bolt as it’s being lifted. Once the new crossarm is on the pole and all the bolts are tightened, the wire and the handline will be lifted and placed on the arm. The wire ties will be sent up on the handline, and the lineworker will tie in the wire. The lineworker will climb down after completing all the work in the air. Once down, he’ll remove his belt and hooks and pack them away. The lineworker on the ground will now be getting the handline ready to store until it’s needed again. All the tools that were used are put back in the truck and packed away. Lastly, they will remove their grounds.
11:45 p.m.: Repairs complete.
Now you might see the lineworkers drive by a third time. This is good news because they are headed for the breaker, and you are about to get your power restored. Once they get to the breaker, they call into our 24-hour Power Control Center and get clearence to re-energize. Power Control will check to ensure no one else is working on the line and then give them clearance to try the breaker, or in some cases utilize our remote monitoring and control system (SCADA) to operate the breaker from our office. At this time, the breaker will be closed, and your power will be restored.
12:05 p.m.: Power restored. Outage over.
Keep in mind that this is just one scenario; not every outage is the same. Each outage varies in time for restoration. This example outage took around five and a half hours to restore. It could have been even longer if the tree had broken a pole.
1:00 a.m. Lineworker returns home, safe and sound.
We work for you, our members.
We’ve become so dependent on electricity that every outage, whether short or extended, can be stressful for those without power. The longer outages last, the more stressful and irritating it can become. We hope this provides a better understanding of the restoration process so you can understand what’s happening while you wait. Just know that your co-op line crews are doing their best to get the lights back on as quickly and safely as possible. Cass County Electric Cooperative and its employees are members of your community. We live in the same neighborhoods. We shop at the same stores. Our kids go to the same schools. If your lights are off, there is a good chance ours are off too. We will always be committed to serving our members and communities by providing safe and reliable electricity—24 hours a day, 7 days a week, 365 days a year.
Below is a time-lapse of the work that goes into a pole replacement. This process took about an hour. Keep in mind this is with a full crew, all material on-site, and favorable weather conditions.