What Is A Power Surge?

Inspire Clean Energy

9 min read

category: Sustainable Living

With electricity all around us, we should become familiar with how it works and what to watch out for. So what is a power surge? What causes a power surge? Are power surges dangerous?

To summarize, a power surge is an unexpected increase in voltage. In some cases, you may not even know a power surge occurred. But there are steps to take that can help protect your home from power surges that you should be aware of.

What is a power surge?

When the voltage flowing through the wall outlet exceeds 169, a power surge typically occurs. Usually wall outlets have 120 volt AC power, however, the voltage can fluctuate. In simplest terms, a power surge is an unexpected increase in voltage. Strong power surges can even result in damage or destruction to electronic devices in your home. To prevent power surges, you should invest in power strip surge protectors or whole home surge protection, which can handle larger voltage discrepancies than strip surge protectors. However, no amount of protection can prevent a power surge or keep your home safe from a lightning strike. So if you know a lightning storm is headed your way, be sure to unplug any electronics1.

What happens during a power surge?

When a power surge occurs, thousands of volts enter your home’s wiring. It can leave some severe damages behind, such as a fried circuit board or a computer crash. But of course, power surges are not all the same. The impact usually depends on the cause of the surge2.

What would cause a power surge?

  • The utility company switching power grids
  • Transmission lines or transformers experience a malfunction
  • Lightning
  • Downed power lines
  • Turning on appliances (refrigerators or microwaves)
  • Internal fluctuations can cause lights to flicker

In some cases, you may notice internal changes, but eventually you will see the extreme impact that a power surge can cause, such as problems with appliances and wiring3.

How do you know if you have a power surge?

Power surges can damage equipment in your home. In some cases, they can be considered a hidden danger. So how do you know if a power surge has occurred? The truth is sometimes you might not know that a power surge has occurred unless it has left damages behind. You cannot prevent a power surge from occurring in most cases, but you can look out for some signs. If you notice the following signs, you should take action to help protect your home4.

  • Power loss or sudden reset
  • Failing or broken electrical devices
  • Tripper circuit breaker

How often does a power surge happen?

There are two types of power surges, internal and external, with a majority of them being internal surges. Some internal surges may not be noticeable and modern electronics can resist the spike of electricity. An internal surge can be caused by appliances or AC units being turned on, but most commonly, they result from faulty wiring. External surges may occur less often but may be more severe. They are often the result of lighting or tree branches coming into contact with power lines5.

Who is responsible for power surge damage?

Power surges can damage electrical appliances. If power surges occur frequently, the device quality can be degraded over time. However, a power surge can rarely cause an electrical fire, which can leave behind severe damage. In some cases, homeowners insurance may cover damages caused by power surges, but in most cases, the homeowner is responsible for internal damages.

What is the difference between a power outage and a power surge?

In simplest terms, a power outage is a loss of power while a power surge increases the voltage. A power surge may cause electronics or appliances to temporarily turn on and off. A power outage may cause appliances and electronics to turn off as well but probably for an extended period. An issue usually causes a power outage with your power supply6.

What is the most common cause of a power outage?

Typically, storms are the most common cause of power outages and surges. However, outages can occur for a variety of reasons such as fires, trees, vehicles crashes, earthquakes, animals, lightning, excavation digging, and high power demand. If you are experiencing a power outage, you should contact your local utility company7.

How long do most power outages last?

In most cases, power outages can be resolved within a day or two. However, if a power outage is the result of a storm, fire, or severe damage, it may take days or weeks for power to be restored. In most cases, your electricity company should be able to provide an estimated timeframe as to when power will be restored after an outage. Power outages can be disruptive. If you live in an area prone to storms or power outages, you may want to consider purchasing a generator8.

Can a bad breaker cause power surges?

Electrical safety features are designed to cut off power if a problem is noticed. A lousy breaker can cause a power surge. Certain things can trigger the shut-off, such as tripping a circuit breaker or GFCI outlets shutting off connections9.

What do you do after a power surge?

If you have the opportunity to notice a power surge, you should not ignore the problem. In some cases, you may be able to diagnose the cause quickly. For example, if you just plugged in an appliance that uses a lot of electricity, and the power surged, it may be obvious what caused the issue. However, if you are unsure of the cause, you should reset and unplug devices and appliances. Once they are unplugged you can reset the circuit breaker. Next, you should assess your home for any damages. Make sure all your devices and appliances are still functioning10.

Is a power surge dangerous?

Power surges can present certain dangers. An overflow of electricity to an appliance may cause the appliance to overheat or break down. In some cases, the appliance may even catch fire. A fire is probably the most serious danger presented by power surges.

Can power surges cause fires?

Yes, power surges can cause electrical fires.

Can power surges damage appliances?

Power surges can damage appliances if they are plugged in. They can also cause damage to power outlets. Homeowner’s insurance may not cover damage caused by a power outage. You may want to consider an extended warranty for appliances that can cover damages caused by power outages.

Can a power surge damage a TV?

Power surges can damage a TV. As we mentioned earlier, in some cases, you may not realize a power surge occurred, that is until you turn your TV on and it suddenly does not work. If your home is experiencing small frequent surges it may take some time for damages to the surface11.

How can power surges be prevented?

Minimizing the risk of power surges can help keep you and your family safe. With proper preparation, there are some steps you can take to prevent power surges. However, in some cases, it may be out of your hands. Here are five ways you can avoid a power surge or surges12:

  1. Maintain and inspect the wiring Faulty or outdated wiring can contribute to power surge problems or make them worse. If you have an older home, it’s essential to have an electrician inspect wiring. You may want to get on a regular schedule for wiring inspections.

  2. Unplug electronics and appliances If possible, unplug as many appliances and electronics as you can, especially if a storm is headed your way. Unplugging electronics and appliances regularly can help prevent surges too. You may want to leave large appliances such as refrigerators plugged in as it may take more energy to unplug and restart them than it would to leave them running.

  3. Install surge protectors An inexpensive way to prevent power surges is to use surge protectors. Valuable electronics such as TVs and computers should be plugged into a surge protector. You can purchase surge protectors at your local home improvement store or convenience store. Examples of a surge protector include power strips and surge protection outlets. These devices can prevent excess voltage from damaging electronics if a power surge occurs.

  4. Install a whole-home surge processor A more invested approach to preventing a power surge is to install a whole-home surge processor. Typically the device is installed at the primary breaker box. It can protect your entire home in the same way that a power strip may protect for certain devices.

  5. Upgrade AC unit and appliances Outdated AC units and appliances may use more power than advanced energy-efficient products that are now available. In addition to saving money on your energy bill, energy-efficient appliances and AC units can prevent power surges because they draw less energy.


If you are researching power surges, you may be concerned about your home's wiring or electricity usage. Ensuring that your home is safe and operating efficiently can benefit you and your family, as well as the environment. Switching to a provider that offers clean energy can reduce your carbon footprint. As an Inspire member, you can access clean energy for one flat price.

So how does it work?

To get started, visit our homepage and enter your home address and/or ZIP Code to discover the beginning of consistent and predictable monthly energy bills.

  1. cloverelectric.com/what-is-a-power-surge
  2. rsandrews.com/What+Happens+During+A+Power+Surge
  3. directenergy.com/learning-center/what-is-power-surge
  4. goodwinelectrical.com/2019/05/19/how-to-identify-a-power-surge
  5. callmendel.com/services/electrical/power-surge-prevention-tips
  6. prairielectric.com/blog/what-causes-power-surges
  7. energized.edison.com/stories/8-common-causes-of-outages
  8. homex.com/ask/how-long-does-a-power-outage-usually-last
  9. happyhiller.com/blog/4-things-that-cause-electrical-issues
  10. acshomeservices.com/blog/2019/february/what-to-do-after-a-power-surge
  11. pennyelectric.com/blog/the-effects-of-power-outages-on-computers-electronics
  12. callmendel.com/services/electrical/power-surge-prevention-tips

Don't worry about climate change— do something about it.

Our clean energy plans are the easiest way to reduce your home's carbon footprint.

Switch to clean energy
Share this article

Inspire Clean Energy

We're on a mission to transform the way people access clean energy and accelerate a net-zero carbon future.

Learn more about Inspire →

Together we can power a greener future

Get renewable today
© 2024 Inspire. All rights reserved.