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Practical Computer Advice
from Martin Kadansky
Volume 15 Issue 8
August 2021
Internet by Candlelight: Are You Prepared for a Power Failure?
The problem
With the many rain, thunderstorms, hurricanes, and tornados making landfall recently, you may have experienced storm-related power outages. Or, your area may have other problems that make power failures an occasional or even frequent problem, regardless of the weather.
Whether you lose power on a regular basis, or you’re simply concerned about the disruption that an outage might cause, read on for my advice on how you can prepare in advance and what to do when it happens.
Note that my focus here is on your computers and other technology. I hope that you’re already prepared by having food, water, flashlights, portable radios, and spare batteries on hand, fueling up your car, etc.
The single most useful thing you can do in advance: Buy a UPS or battery backup unit
When talking to clients who are concerned about power outages, most of the time I recommend that they buy an uninterruptible power supply (UPS), also know as a battery backup.
The main purpose of a UPS is to:
  • Detect that the power has gone out
  • and then immediately switch your computer (and its directly-connected peripherals like an external monitor, USB hub, etc.) over to be powered by the battery inside the UPS.
  • This gives you a few minutes to save and close your work, instead of possibly losing whatever you were working on,
  • after which you can shut down your Windows or Macintosh computer in an orderly manner before the UPS battery runs out.
This idea was developed years ago for desktop computers (and their external monitors), long before battery-powered laptops, smartphones, and tablets were common. If you use a laptop or iPhone, iPad, or Android, then having a UPS is less critical since the risk of losing your work is much lower (as long as the battery still works and you keep it reasonably charged), but you might still find a UPS to be useful to keep your main devices charged and to power some of your other devices during a power failure.
A UPS is a combination of a surge protector and a big internal battery, so it’s taller (thicker) and heavier than a regular surge protector. The consumer-level models typically have 6-8 outlets for your equipment, divided into two separate types:
  • Power outlets that will run on the battery when the power goes out, which are also surge-protected
  • Power outlets that are only surge-protected, and will not provide any power during a power failure
In order to make the best use of your UPS, you’ll plug the appropriate device into each type of outlet.
Choosing a UPS that fits your needs
In order to assess your needs, you will need to determine:
  • Voltage level: What does your equipment require? In the US it’s 120V.
  • Important equipment: Which devices do you absolutely need to keep running (for a limited time) during a power outage?
  • Power draw: How many watts (or volt-amperes) of power does each of those devices consume?
  • Running time: For how long (in minutes) do you want your UPS to power those devices?
  • Extra capacity: Do you want to add any additional capacity in case you’ve underestimated your needs or they grow in the future?
Once you have the above information, you can then shop for an appropriate UPS. If you’re not sure how to do this, talk to someone you know and trust for help or contact the UPS manufacturer.
Expect to spend somewhere between $50 and $300, depending on your needs, and roughly $40 or more for replacement batteries as they wear out. There are many good brands on the market, including APC (American Power Conversion), CyberPower, Tripp Lite, etc.
Additional things you should know
Keep the following in mind:
  • During a power failure, a UPS will only supply power for a relatively short time, usually measured in minutes, not hours. Don’t expect to continue working for days on end.
  • You won’t know exactly how much “running time” you’ll get from a UPS until you set one up and test it with your actual equipment.
  • You can simulate a power failure by temporarily unplugging your UPS from its wall outlet.
  • For many clients (who may not keep a flashlight and batteries nearby) I also recommend that their desk lamp be plugged in to their UPS in case the power goes out after dark.
  • In addition to buying a UPS for your computer, consider buying another one for your internet modem and router, which (if your regular internet service might still be active during a power failure) would also keep your internet connection (and Wifi network) active for a limited time.
  • Devices that consume a lot of power (like a laser printer or an air conditioner) or that are less important (like an inkjet printer or a fax machine) should not be plugged into the same UPS as your computer.
  • Your UPS won’t last forever. You’ll probably have to replace the battery in 3-5 years, and the entire unit in 5-7 years.
  • You can buy additional UPS units to power other devices during a power outage as necessary.
  • Make sure that each UPS is plugged directly into a wall outlet.
  • A UPS will not solve every power-related problem. Talk to an electrician or other professional if you experience brownouts or other issues.
Additional important things that you can do in advance
First, do your groundwork:
  • All of your wiring should be up to code.
  • All of your power outlets should be properly grounded.
  • All power cords should be plugged in properly, e.g., all 3-prong plugs should have their ground prongs actually connected to ground.
  • All of your surge protectors should be less than 4-5 years old.
Then, in order to prepare in advance for power outages, I recommend:
  • Fully charge all of your devices that run on rechargeable batteries, including laptop computers, smartphones, tablets, cordless headsets, cordless phones, cameras, etc.
  • For all of your devices that run on regular (AA, AAA, etc.) batteries, including cordless keyboards, mice, voice recorders, etc., check that their batteries have a good charge and haven’t leaked.
  • Some internet modems (including Verizon FiOS Optical Network Terminals or ONTs) have their own battery backup units, so you should also check them periodically and replace their batteries as appropriate.
  • If it’s likely that your cell phone service will be active during a power failure, I recommend that you practice activating your “mobile hotspot” and switching to it, in case your regular internet service is down.
  • Make a list of all of the clocks that will need to be reset after the power comes back on.
  • Document your fuse box or circuit breakers so that you’ll know which lights and outlets each circuit controls.
  • Take photos of your equipment (and your furniture, car, house, etc.) for insurance purposes.
During a power failure
Keep your computer, cell phone, and tablet usage to a minimum to conserve your batteries, since you won’t know how long the power will be out.
When the power goes out for more than a few minutes, it’s also prudent to unplug any expensive devices and appliances (that aren’t already on a surge protector or UPS), because when power is restored there can be surges that might damage your equipment. After the power comes back on, wait at least 10 minutes before plugging those appliances back in to try to avoid those surges.
Also, if the battery for a critical device (like your cell phone) is running low and you also have a UPS, you could plug that device’s charger into your UPS, but remember that that will reduce the running time for any other devices on that same UPS.
Should you get a generator?
If you live in an area where power outages are frequent, or if someone in your family relies on medical devices that must be powered continuously, investing in an outdoor gasoline- or diesel-powered standby generator might make sense.
Where to go from here
Try these searches, replacing “XYZ” in the first one with the name of your local power company, e.g., Eversource, NStar, PG&E, etc.
How to contact me:
phone: (617) 484-6657

On a regular basis I write about real issues faced by typical computer users. To subscribe to this newsletter, please send an email to martin@kadansky.com and I'll add you to the list, or visit http://www.kadansky.com/newsletter

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I love helping people learn how to use their computers better! Like a "computer driving instructor," I work 1-on-1 with small business owners and individuals to help them find a more productive and successful relationship with their computers and other high-tech gadgets.

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