Backup Power for Apartments and Renters: What Actually Works

Most backup-power advice assumes you own a house with a garage, a yard and an electrical panel you’re allowed to modify. If you rent an apartment, condo or flat, almost none of that applies. You can’t install a standby generator, you probably can’t touch the wiring, and you definitely can’t run a gas generator on a balcony.

The good news: renters have more options than ever, mostly thanks to portable battery power stations. This guide covers what works in an apartment, what to avoid, how to size a system, and how to keep your landlord (and your neighbours) happy.

Short version (general guidance): For most renters, a portable battery power station in the roughly 1,000–2,000 Wh range, plus a few good-quality power banks and LED lanterns, covers the essentials through a typical outage. Skip gas generators entirely — they’re unsafe in and around apartments.

Rule #1: No fuel-burning generators in or around your apartment

This is the one non-negotiable. The US Consumer Product Safety Commission says most portable-generator incidents reported to it involve carbon monoxide (CO) poisoning from generators used indoors or in partially enclosed spaces. It warns never to use a generator inside homes, garages, crawlspaces or sheds — “even when using fans or opening doors and windows” — and to keep generators at least 20 feet from doors, windows and vents (CPSC safety alert). In a 2024 hurricane warning, CPSC added that you should not run a generator on an outside porch or in a carport because they’re too close to the home (CPSC).

For most apartments, there is simply nowhere that meets that standard — and CO can drift into your neighbours’ homes too. Many leases and building codes also ban storing fuel indoors. The same caution applies to using grills, camp stoves or other fuel-burning devices indoors, which the Red Cross also warns against (Red Cross).

Battery power stations produce no exhaust, which is why they’re the go-to solution for renters.

What renters typically need to power

Start with a list. Most apartment dwellers care about some combination of:

• Phones and laptops — communication and work
• Wi-Fi router and modem (if your building’s internet still has power upstream)
• Lights — ideally efficient LED
• Fridge (and maybe a small freezer)
• Medical devices — especially CPAP machines
• Fans or a small heater — comfort, depending on the season
• Aquarium pumps, a pet’s heat lamp, or other “must stay on” devices

Each of these draws a very different amount of power. Phones and routers are tiny loads; heaters and air conditioners are huge.

Sizing a power station: watts vs watt-hours

Two numbers matter on every power station:

• Output (W) — how much power it can deliver at any moment. It must exceed the combined draw of everything you plug in at once, plus the start-up surge of anything with a motor or compressor.
• Capacity (Wh) — how much energy it stores. This determines how long it lasts.

A rough runtime estimate (general guidance) is: usable Wh ÷ average watts drawn = hours. Many calculators assume about 85% of the rated capacity is usable after inverter losses.

Example loads from published sources

Device	Typical draw quoted	Source
CPAP, no heated humidifier	about 25–60 W	PowerStationMatch
CPAP, humidifier on	about 60–100 W	PowerStationMatch
CPAP without humidifier, 8-hour night	about 240 Wh at the machine (≈30 W)	OutageMath
Small 5,000 BTU window AC	about 450 W running, ~1,100 W to start, ~225 W average as it cycles	OutageMath
Fridge, Wi-Fi, two phones, three LED bulbs	about 2.3 kWh per day, before safety margin	OutageMath

These are estimates from calculator sites, not our own measurements — your devices will differ. Check the label or manual on each one, and if you can, measure with an inexpensive plug-in watt meter.

Typical size bands (general guidance)

• About 300–500 Wh: phones, laptops, LED lights, router, and a CPAP for a night without the humidifier. Light and easy to store.
• About 1,000–2,000 Wh: adds a fridge for many hours to a day, plus the essentials above. One sizing guide recommends 1,000–2,000 Wh for “home backup that runs a fridge and essentials through a blackout” (WhatPowerStation). This is the sweet spot for most renters.
• 3,000 Wh and up: multi-day outages or comfort loads such as a window AC. These units are heavy — often too heavy to carry up stairs easily — so think about where it will live.

The apartment-friendly backup kit

Here’s a practical, layered setup for renters (general guidance — adjust to your needs and budget):

Layer 1: Power banks and lights (everyone should have these)

• Two or three USB power banks kept charged, for phones.
• LED lanterns or headlamps with spare batteries — far safer than candles.
• A battery or hand-crank radio for emergency information.

Layer 2: A portable power station

• Choose capacity based on your list above; 1,000–2,000 Wh suits most.
• Prefer LiFePO4 (lithium iron phosphate) batteries. Comparison sites report LiFePO4 power stations are rated for thousands of charge cycles versus hundreds for older NMC lithium-ion designs, and are more thermally stable (Jackery explainer; Popular Mechanics).
• Look for a pure sine wave inverter (standard on reputable units) for sensitive electronics and medical devices.
• Look for UPS or pass-through mode if you want your router or CPAP to switch to battery automatically when the power cuts. Switchover times vary by model — check the documentation.

Layer 3: Recharging during long outages

• A folding solar panel on a sunny window or balcony can top up a power station during the day. Output through glass and in shade is much lower than the panel’s rating, so treat it as a bonus, not a guarantee.
• A 12 V car charging cable lets you recharge from your car (run the car outdoors only, never in an enclosed garage).

Keeping your fridge cold

The fridge is the biggest “essential” load for most renters. A few tips (general guidance):

• Keep the door shut. A full, closed fridge stays cold for hours without power.
• Run it on the power station in intervals if capacity is limited — for example, an hour on, an hour or two off — and keep a fridge thermometer inside.
• Check the surge rating. A fridge compressor needs a brief burst of power to start; OutageMath and others note this can be around 1,000 W or more for a full-size fridge. A power station with too little surge capacity will shut off when the compressor kicks in.
• Follow official food-safety guidance from your local health authority on what to discard after an outage.

CPAP and medical devices

If you rely on a CPAP, oxygen concentrator or other powered medical device, plan carefully:

• Turn off the heated humidifier during outages if your doctor agrees — it can roughly double the power draw (OutageMath).
• Use a DC adapter if your machine supports one. Running from the power station’s 12 V output avoids inverter losses; several sizing guides say this extends runtime significantly.
• Test a full night on the power station before you need it.
• Register with your utility if it offers a medical-priority or vulnerable-customer list, and talk to your doctor or equipment supplier about a backup plan. Oxygen concentrators in particular can draw a lot of power.

Talking to your landlord

You generally don’t need permission to own and use a battery power station, any more than you need permission for a laptop. But it’s worth checking:

• Your lease for rules about batteries, solar panels on balconies, or fuel storage.
• Building rules on anything attached to a balcony or railing.
• Fire safety: store your power station on a hard, stable surface away from heat sources, and follow the manufacturer’s charging guidance.

What you should not do as a renter is modify the electrical system — no transfer switches, inlets or rewiring — unless your landlord agrees and a licensed electrician does the work. See our guide to connecting a power station to a house safely for why.

A simple renter’s outage checklist

1. Power banks charged; power station kept above about 80% (check the manual for long-term storage advice).
2. Lanterns and headlamps where you can find them in the dark.
3. Fridge thermometer in place.
4. CPAP/medical device tested on battery.
5. Router and modem on a UPS or the power station’s pass-through outlet.
6. Your utility’s outage map bookmarked and outage alerts turned on.
7. Phone numbers written down on paper.

The bottom line

Renters can’t install generators or rewire their homes — and shouldn’t try. But a well-chosen battery power station, backed by power banks, LED lighting and a simple plan, keeps the essentials running through most outages, safely and quietly. Size it from your own device list, prioritise medical needs, and test before the lights go out.

For the full range of choices, see home backup power options compared. Want to weigh up bigger, permanent options for when you own a home? Read Home battery vs generator: the real costs.

This article is general information, not professional, medical or electrical advice. Follow manufacturer instructions, your lease and local regulations.

Frequently asked questions

Can I use a generator in an apartment?

No. The CPSC warns never to run a generator indoors, in garages or on porches and to keep it at least 20 feet from doors, windows and vents because of carbon monoxide. Battery power stations produce no exhaust and are the safe option for apartments.

What size power station do I need for an apartment?

As general guidance, about 300 to 500 Wh covers phones, lights, a router and a CPAP for a night without humidifier, while about 1,000 to 2,000 Wh adds a fridge for many hours. List your devices and their watts to size it properly.

Do I need landlord permission for a portable power station?

Generally no more than for a laptop, but check your lease and building rules, especially about balcony solar panels. Do not modify the building's electrical system without the landlord's agreement and a licensed electrician.

How can I keep my fridge cold in an apartment during a power outage?

Keep the door closed, run the fridge from a power station with enough surge capacity, consider running it in intervals if capacity is limited, and keep a fridge thermometer inside. Follow your local health authority's food-safety guidance.