Size my backup

How to prepare for a power outage

Most of the work happens before the storm. List what in your home needs electricity, decide how you'll keep the important things running, and stock what you need for a few days without power.

Published , by Alex Rowan

1. List what needs electricity

Ready.gov’s first step is an inventory of everything in the house that runs on power. Walk through each room. The obvious items are the refrigerator, the lights and the phone chargers. These are easier to forget:

  • A gas furnace still needs electricity for its blower fan and controls, so it stops when the power does.
  • On a well, the well pump supplies every faucet and toilet.
  • A sump pump quits during the same storms that fill the pit.
  • Medical devices such as a CPAP, oxygen concentrator or powered wheelchair, and medicine that needs refrigeration.
  • The Wi-Fi router and modem, and a home phone. Ready.gov suggests checking whether your landline works without power and how long its battery backup lasts.
  • The garage door opener. Find its manual release now, in daylight.

Then mark each item as must run, nice to have or can wait. The first group is what you size backup power around.

2. Decide how you’ll keep it running

There are four common ways to power a home through an outage:

  • A portable power station: a battery with outlets, recharged from the wall, solar panels or a car. Quiet and safe indoors, but it only lasts as long as its charge.
  • A portable generator: runs on gasoline or propane for as long as you refuel it. It must run outside, at least 20 feet from the house.
  • A standby generator: installed permanently, runs on natural gas or propane and starts on its own when the grid fails.
  • A home battery: wired into your electrical panel by an installer, often paired with solar.

The power station vs generator guide compares the two portable options. To see how much capacity your must-run list needs, switch those appliances on in the runtime calculator. It shows the total load, the startup surge and the hours each battery size lasts.

Buy and test whatever you choose before you need it. Charge the power station fully, or start the generator and run a real appliance from it.

3. Get the safety gear in place

  • Carbon monoxide alarms on every level of the home and outside sleeping areas, battery-powered or with battery backup (Ready.gov, CPSC). The CPSC says interconnected alarms are best and that alarms should be certified to UL 2034, IAS 6-96 or CSA 6.19.01. Test them monthly.
  • Smoke alarms on every level and inside each bedroom (CPSC).
  • Flashlights for everyone in the house, with spare batteries (Ready.gov).

4. Stock water, food and medicine

  • At least 1 gallon of water per person per day for several days, for drinking and sanitation (Ready.gov).
  • Nonperishable food that doesn’t need cooking, in case your stove is electric.
  • A cooler, plus ice packs or containers of water kept frozen. Appliance thermometers in the fridge and freezer tell you afterward whether the food stayed safe. The food safety guide covers the details.
  • Ready.gov suggests talking to your medical provider about a plan for powered devices and refrigerated medicine, including how long each medicine can stay at higher temperatures.

Many utilities keep a list of customers who rely on powered medical equipment. Ask yours whether it has one and what it offers, and plan your own backup either way.

5. Keep phones and news working

  • Keep power banks charged. A power station can recharge a phone many times over.
  • Sign up for your utility’s outage alerts and save its outage line and app.
  • A battery or hand-crank radio keeps you informed if the cell network goes down.

6. If you’ll use a generator, set it up now

  • Pick the spot: outside, at least 20 feet from the house, away from windows, doors and vents, with the exhaust pointed away from buildings (CPSC, NFPA). Never in the garage, even with the door open.
  • Buy heavy-duty outdoor extension cords rated above the total wattage you’ll connect, and long enough to reach from that spot (CPSC).
  • Plan for rain. The CPSC suggests an open, canopy-like cover on a dry surface. The rain guide explains what manufacturers allow.
  • Store fuel outside living areas, in labeled, non-glass safety containers, and away from fuel-burning appliances such as a gas water heater in the garage (CPSC).
  • Look for a model with a carbon monoxide shut-off, which stops the engine when CO builds up around it (CPSC).
  • To run house circuits, have a licensed electrician install a transfer switch or an interlock kit before the season. Never backfeed through an outlet. The backfeeding guide covers both options.