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Will your WiFi survive the outage?
Outer Banks power loves a dramatic flicker — and every one sends your modem into the 10-minute reboot dance. Pick what needs to stay on, pick a battery backup, and see real runtime numbers (honest ones, not the box’s marketing).
1. What needs to stay on?
Tap everything you’d plug into the battery. Typical wattages are pre-filled — edit them below if you know yours.
2. Pick the battery backup
VA sizes are calibrated to published APC runtime curves — expect real-world results near these, not the “up to” number on the box.
Grab-one-today picks
For modem + router, a 600VA unit is the sweet spot. Starlink or cameras in the mix? Go 1500VA — or a lithium power station for real outage hours.
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Want the outage-proof version installed?
We set up whole-home backup for internet and cameras — the right UPS on the right gear, wired clean, labeled, and tested. One visit, and the next flicker is a non-event.
(252) 686-1451Good to know
What a UPS actually does (it’s mostly about blips)
Most OBX “outages” are 2-second flickers — but every one sends your modem and router into a 10-minute reboot dance, drops the video call, and knocks the cameras offline. A UPS bridges those gaps seamlessly, so the biggest win costs the least: even the smallest unit turns flickers into non-events. The hours of runtime for real outages are the bonus.
Why your internet often still works when the power’s out
The cable and fiber networks have their own backup power, so the signal at your wall frequently stays live even when your neighborhood is dark. That’s exactly why battery-backing the modem and router pays off: a fiber ONT sips about 10 W, so even a small UPS keeps a whole house connected for a long time. If the outage is big enough to take the provider’s plant down too, your phone’s cellular data is the fallback — towers carry battery and generator backup.
Sizing rule of thumb
Ideal-world runtime is battery watt-hours ÷ load watts — real world delivers roughly 60–70% of that after inverter losses, and less as you push a unit hard. The lever that matters is the load: halve the watts and runtime more than doubles. That’s why the pros put only the modem and router on battery instead of buying a monster UPS for the whole TV cabinet.
Salt air and the 3–4 year battery clock
UPS batteries are consumables — figure 3–4 years here, a bit less in humid, salty garages and utility closets. When one starts chirping, it’s the battery telling you it’s done; most units take a cheap replacement cartridge rather than a whole new UPS. Press the test button a couple of times a season so hurricane week isn’t when you find out it’s dead.