What’s the difference between a blackout and brownout?
The impact of outages on your devices, internet and WiFi
The lightning flashes. The thunder booms. The rain pours.
The lights flicker. The house goes dark, and just like that, you’re scrambling for candles and flashlights.
Power-disrupting extreme weather events can bring in a deluge of disarray—and that includes potential damage for your electronic devices. But don’t be shocked—you have the power to prevent it.
If the power is out, you’re likely dealing with one of two scenarios—blackout or brownout. Understanding the difference is key, because each can impact your electronics differently.
Shedding light: Definitions and differences
Blackout: Widespread, total loss of electrical power.
Common causes: Structural damage to infrastructure from natural disasters, power plant equipment failure and sometimes by hacking the computer systems that keep the power grid online.
Brownout: Temporary reductions in power during times of high demand that exceeds a utility company’s output capacity.
Common causes: Usually a planned event by utility companies to manage spikes in demand, reduce strain on electrical infrastructure and avoid full-scale blackouts.
The key difference: During a brownout, system capacity is decreased and voltage is typically reduced by at least 10 to 25 percent. Some electrical devices like light bulbs might still operate in a limited capacity.
What outages mean for electronics
The real risk to your devices is not the outage itself—it’s actually electrical surges or spikes. Surges are most common during brownouts (as the power regularly fluctuates) or in the first few moments after the power is initially restored after a blackout.
Electrical surges can instantly overload or short out the circuits of plugged-in electronics. That’s why it’s crucial to unplug all non-essential devices during any outage event. Dimming or flickering lights is a good warning sign an outage is on the way.
What about the internet and WiFi?
It is highly unlikely you will have internet service or WiFi during a brownout.
Here’s why: Brownouts are subject to unpredictable voltage fluctuations. Though your device might power up, routers, modems and connected devices like computers are highly sensitive to voltage fluctuations. Brownouts may cause these devices to repeatedly and rapidly power cycle, and that could result in permanent damage if connected to power.
The bottom line? It’s a good idea to fully unplug these devices until power is fully restored.
More power to you: What you can do
Safely pull the plug on everything from desktop computers (external monitors, too), laptops, game consoles, printers, routers, TVs, radios, and don’t forget items like your microwave or electric keyboard.
It’s a good habit to have your devices charged and ready in advance of inclement weather. But that’s not always top of mind when your most important concern is the safety of your family and home. That said, include this list with your storm preparedness plan:
- Use alternate power sources such as portable chargers, battery banks or solar chargers. They offer several hours of battery life so you can use your devices in an outage.
- Keep extra batteries on hand.
- Use surge protectors for all plug-in electronics.
- To avoid service interruptions, consider a portable generator or an uninterruptible power supply (UPS). Consider cost, size and how much power you need during an emergency—it will likely be based on how many kilowatts (kW) you use per day and what you think is necessary.