Before we start, it’s important to state the following as clearly as possible: if you are in an area that is under mandatory evacuation orders because of an approaching hurricane, stop reading this article and get out. Don’t try to ride out the storm. If you don’t leave now, you might die. Your stuff isn’t worth your life. Get out now. You can read this later, when you’re safe.

From personal experience, one of the most jarring things about being stuck in a storm is the disconnection from reality and the removal from normalcy. Familiar and safe surroundings become menacing when power is lost and the wind is howling. Especially for folks used to being online all the time, losing power in a disaster and being cut off from communication can be terrifying.

While there’s not much to do for a multi-day power outage aside from buying a generator—a solution that comes with its own problems, since generator-related deaths tend to outnumber storm-related deaths in any given US-landed hurricane—there is a quick way to bridge the power gaps posed by a few isolated hours without power here and there: hook your infrastructure components up to an uninterruptible power supply.

The juice is loose

UPSes aren’t just for computers. Conventional wisdom is that you absolutely should have a UPS capable of keeping your desktop computer(s) online for at least a few minutes in a power outage; however, the same UPS that works for your desktops will also work for your networking gear. This works even better if your main computer is a laptop, which already has its own big battery built in.

If power is out for days, then a UPS for your network gear won’t help you.

Something like this Cyberpower UPS will do nicely (I know this one will work well because I have several of them, one of which is plugged into my cable modem, router, and power-over-Ethernet switch). The trick is that most of your home infrastructure devices are low power, pulling maybe a dozen watts at most. The same UPS capable of keeping your desktop computer and monitor on for 15 minutes will likely power your cable modem, router, and Wi-Fi access points (if separate) for 90 minutes or more.

Your ISP will generally stay online during outages, because most ISPs’ infrastructure is protected by backup power—usually with banks of batteries and a large non-portable diesel generator with underground tanks. If you can keep your cable modem, router, and Wi-Fi online when the power goes out, you’ll almost always find that your ISP is also online—and you’ll keep your Internet access.

For a while, at least.

What to plug in

Here’s a non-exhaustive list of devices you should hook up to a UPS to last through short (as in 90 minutes or less) outages:

Cable modems

Routers, if separate from cable modems

Wi-Fi access points, if separate from your router (like if you're using Ubiquiti access points, for example

Any network switches connecting your cable modem or router or Wi-Fi access points to each other, especially PoE switches

How this will and won’t help

First, from a perspective of access, keeping Wi-Fi available rather than having to fall back to cellular data during a storm means you have a better chance of staying online. Cellular access depends on backup batteries or generators at multiple affected locations staying online—you need the towers up and operating, you need their backhaul links operating, and you need the power up at the uplink point where the cell towers' backhaul connects to the rest of the Internet. For your home's Internet connection to stay up, there are (typically, but not always) fewer links in the upstream chain that need to stay powered—usually just your ISP's local termination point.

Staying on Wi-Fi in your home usually also means faster speeds, fewer delays due to cellular signal interference or congestion, and no need to argue about cellular data overages with your carrier afterward. It also means non-cellular devices like laptops, desktops, and many tablets can still connect to the Internet, rather than reducing you to only using cellular data-equipped phones.

If you’re in an area where power is flickering on and off, having your networking gear connected to a UPS will at the very least stop your gear from power cycling with the rest of the house; it’ll also obviously keep your Internet connection up and operational.

If you’re in a multi-hour power outage, this will help a bit less. A 1500VA/900W UPS like the one I linked above lasts me and my networking gear for about 90 minutes, so that’s about the longest power outage you can bridge with it. However, once power is restored, the UPS will recharge over the course of a couple of hours. If power is intermittent across multiple days, this will still keep you online for most of it.

If power is out for days, then a UPS for your network gear is of limited utility.

Recharging and the question of generators

Ah, you ask, but what if you have a generator? A generator definitely would keep your UPS topped up and your infrastructure online, though during a multi-day outage you likely have other more pressing needs for power (like keeping food fresh) than to spend it on Internet connectivity.

At the same time, though, normalcy—even the illusion of normalcy—has a hugely calming effect during times of crisis. If you have a generator, using some capacity to stay online (assuming your ISP stays online) is not necessarily a bad thing, especially if it helps you to stay in touch with friends and family or communicate with local authorities.

Just be very, very careful. Improper use of a generator can kill you and your family, and that’s not a joke or exaggeration.