Power Backup at Home: Keep Internet and Laptop Alive

It’s a familiar scene for anyone who works or learns from home: you’re deep into a video call, or maybe the kids are finishing homework online, when—bam—the lights flicker, your router dies, and suddenly everyone’s offline. Sometimes it’s a planned outage, sometimes a squirrel decides to take out a transformer for fun. Either way, you’re stuck.

I’ve been there more times than I’d like. After the third “Sorry, my power went out…” in a week, I decided enough was enough. The goal: keep my internet and laptop running for at least an hour during any outage, without spending a fortune or burning the house down. Here’s how I built a simple, reliable backup system that’s kept me connected through everything from minor blips to full-blown storms.

What You Actually Need to Back Up

Let’s keep it practical. Most homes don’t need a full-scale generator. For remote work, you just need to keep:

Your laptop (which usually has its own battery, but it’s nice to keep it topped up)
Your internet gateway devices: typically a router and an ONT (Optical Network Terminal) if you have fiber

Forget about powering the fridge or entire house—that’s a different beast. We’re aiming for essentials only here.

“The first time I lost connection mid-demo, my client joked that I must live in the Stone Age. Not my proudest moment.”

Case Study: My Simple UPS Setup

My setup is basic but effective:

A small offline UPS (Uninterruptible Power Supply), rated at 650VA/390W
2 x surge-protected outlets (one for router, one for ONT)
USB output for phone charging (bonus!)
All devices consolidated on a single power strip for easy management

This keeps my internet gear running for about 2.5 hours, and gives my laptop a full recharge. Total cost? About $70—less than a nice dinner for two.

Sizing Your Backup (VA, Watts, and Runtime)

The most confusing part is figuring out how big a UPS you need. Here’s how to break it down:

Step 1: Find Device Power Ratings

Laptop charger: Usually 45–65W (check the brick label)
Router: 7–15W (find the adapter rating; most are 12V/1A = 12W)
ONT: 5–10W

Step 2: Add 20% Overhead

Multiply the sum by 1.2 to be safe.

Step 3: Convert to VA (Volt-Amps)

UPS units are rated in VA. Divide your total watts by 0.6 (since most small UPS units assume 60% efficiency).

Example:

Laptop charger: 60W
Router: 12W
ONT: 8W
Total: 80W x 1.2 = 96W
96W / 0.6 = 160 VA

Reality check: Even the smallest UPS (400VA) will handle this load easily.

Step 4: Estimate Runtime

Most 600–700VA UPS units (about 350–400W) have a 7Ah or 9Ah battery at 12V—that’s about 84–108Wh.

So, if your total load is 80W:

Runtime = Battery Wh / Load W = 84Wh / 80W = about 1 hour

But your real load is usually lower, since your laptop battery will take over much of the time.

Wiring Diagram: The Simple Way

Here’s how my setup looks:

Simple UPS wiring diagram for router, ONT, and laptop

PIN IT

Wall outlet → UPS input
UPS output → Power strip
Power strip → Router, ONT, laptop charger

If you want to get fancy, you can wire your router and ONT to a dedicated DC UPS (these are more efficient), but for most people, an off-the-shelf AC UPS is easier.

Safe Placement and Operation

UPS units aren’t complicated, but there are a few safety tips:

Keep the UPS on a hard, flat surface—never cover vents
Don’t put the UPS in a closed cabinet (they get warm)
Replace the battery every 3–5 years (most beep when it’s time)
Plug only low-power devices (don’t add printers, heaters, or monitors!)

Test Routine: Don’t Skip This!

I schedule a quick test every 2 months:

Unplug the UPS from the wall (with everything attached)
Set a timer for 30 minutes
Check if internet and connected devices stay up
Plug back in, and confirm battery recharges

Bonus: You’ll find out quickly if your battery is dying.

Quick Checklist: Your 15-Minute Backup Plan

Step	Action
1. Assess devices	List everything you want to back up (router, ONT, laptop charger)
2. Check power ratings	Read watts on adapters or use a plug-in power meter
3. Buy UPS	Choose 600–800VA for most setups
4. Safe placement	Keep UPS cool, accessible, and off the floor
5. Plug in	Connect devices, test everything
6. Test every 2 months	Unplug from wall and verify backup works