Power outage preparedness — a 72-hour home plan

A blackout is a power outage that does not end in twenty minutes. Ready.gov sets out what an extended one does: it disrupts communications, water and transportation; closes stores, gas stations, ATMs and banks; causes food spoilage and water contamination; and prevents the use of grid-powered medical devices.

You do not need to expect a catastrophe to prepare for one. Storms, ice on the lines, a failed substation — the causes are ordinary, and so is the preparation: water, food that needs no cooking, light, warmth, a way to receive information, and some cash. Not a generator or a basement full of canned goods.

The European Commission's 2025 preparedness strategy commits to guidelines aimed at population self-sufficiency of a minimum of 72 hours. Ready.gov puts it plainly: after an emergency you may need to survive on your own for several days. Treat 72 hours as the floor to build from, not a forecast of how long the lights will be off.

Water — before and during

Ready.gov's kit guidance is one gallon (about 3.8 liters) per person per day, for drinking and sanitation. Three days for a family of four is twelve gallons — roughly 45 liters, less space than most people expect for the most important item on the list.

Your faucets are not independent of the grid. Wherever an electric pump is involved — high-rise buildings, private wells, some rural networks — the water stops when the power does, and Ready.gov lists water disruption and contamination among an outage's direct effects. If one is announced in advance, fill the bathtub first: that water only has to flush a toilet and wash hands. Once your 72 hours are covered, the Red Cross recommends building toward two weeks at home.

Food that needs no cooking

Stovetops and ovens stop with the grid, so an outage stock is not ingredients — it is food you eat straight from the package. Ready.gov's kit list calls for a several-day supply of non-perishable food plus a manual can opener — the piece people forget. A can without one is not a supply.

Choose what your household actually eats — canned fish and beans, crackers, nut butter, dried fruit, energy bars. The Red Cross adds a sequencing rule: eat your fresh, perishable food first and keep the shelf-stable stock for later.

The fridge and freezer clock

Two numbers are worth memorizing. FoodSafety.gov states that a refrigerator keeps food safe for up to 4 hours during a power outage, and that a full freezer holds a safe temperature for approximately 48 hours — 24 hours if it is half full and the door remains closed. The Red Cross gives the same three figures; Ready.gov gives the same four- and 48-hour ones.

"Door remains closed" is the whole technique: every opening spends cold you cannot replace. Note the time the power went out — after two days you will not reconstruct it. The Red Cross recommends coolers with ice, and a thermometer in the fridge or freezer so you read a number rather than guessing.

Light — flashlights, not candles

The Red Cross guidance is a single sentence: use flashlights, not candles. Ready.gov asks for one flashlight per household member — a shared flashlight is a flashlight for nobody. Stock the spare batteries Ready.gov lists as a basic kit item, and standardize on one cell size across flashlights and radio.

Heat, cold, and carbon monoxide

In winter a home cools slowly but steadily, because a furnace's pump and controls need electricity even when the fuel does not. Gather everyone into one small room, close the doors to the rest of the home and cover the windows at night. Layers, hats and sleeping bags do more than any improvised heater.

This part allows no compromise, so here it is in Ready.gov's own terms. Generators, camp stoves and charcoal grills should always be used outdoors and at least 20 feet (about 6 meters) away from windows — and generators and fuel at least 20 feet from windows, doors and attached garages. The Red Cross says the same from the other direction: never use a generator, outdoor stoves or heaters indoors. There is no version of this in which an open window or door makes indoors acceptable.

Never use a gas stovetop or oven to heat your home. Ready.gov is explicit that this increases your risk of carbon monoxide poisoning, and also raises the risk of fire and burns and can damage the appliance. A stove is for cooking.

The reason for all of it is carbon monoxide, which Ready.gov describes as a colorless, odorless gas that can kill you, your family and pets. You will not see it, smell it, or wake up because of it. Install carbon monoxide detectors with battery backup in central locations on every level of your home; the Red Cross asks for one per level. If a detector sounds, or if anyone develops an unexplained headache, dizziness, nausea or drowsiness, get everyone outside into fresh air and call your emergency number.

If you do run a generator, Ready.gov adds: keep it dry, since touching a wet generator can cause electrical shock; use heavy-duty extension cords; let it cool before refueling, because spilled fuel ignites on hot parts; and follow the manufacturer's instructions.

In summer the problem inverts — without air conditioning or fans a home overheats. Shade the sunny windows, ventilate at night, drink more water. If your home becomes too hot or too cold to stay in safely, or someone depends on a powered medical device, leaving is the right call rather than a failure: Ready.gov advises going to a community location with power. That is when a packed bug-out bag pays off.

Communication and information

Your phone has two problems at once: it drains, and it loses signal. Cell towers have backup power, but not for days, and Ready.gov lists disrupted communications among an outage's first effects.

So the first device on the list is a radio. Ready.gov's kit calls for a battery-powered or hand-crank radio; the Red Cross asks for devices that work without home power — a crank or battery radio, a non-cordless landline, and chargers and batteries for phones. A radio keeps receiving official information after the mobile network has given up.

Budget your phone's power the way you budget food: one household phone on at a time, the rest off in reserve, data and brightness down, texts rather than calls. The Red Cross recommends a paper copy of your contact list, because contacts inside a dead phone do not exist. Ready.gov also suggests checking whether your home phone works without grid power.

One honest caveat: if you are relying on offline maps — in Strongstead or any other app — the tiles have to be downloaded while you still have internet. Nothing downloads after the network goes, and the same applies to documents kept in the cloud.

Cash and payments

A card terminal needs power and a data connection; an ATM needs both. Ready.gov lists closed stores, gas stations, ATMs and banks among the effects of an extended outage, and its kit list includes cash for exactly this reason.

Keep it in small denominations — a store running on a calculator and a cash box cannot break a large bill. A gas pump is electrical too, which is why the Red Cross suggests keeping your car's tank at least half full.

Home utilities — know your shut-offs

This is a section about knowledge, not DIY. Every adult should know where the breaker panel and the main gas and water shut-offs are, and be able to reach them without moving furniture. Ready.gov's kit list includes a wrench or pliers for turning off utilities — useful only if you know what you are turning.

An outage by itself is not a reason to shut anything off. The Red Cross is precise: turn off the utilities only if you suspect damage or if local officials instruct you to, and your gas line can only be turned back on by a qualified professional. If breakers have tripped, have an electrician inspect them first.

Do one thing as soon as the lights go out: disconnect appliances and electronics, because both agencies warn that power can return as a damaging surge. Leave the fridge and freezer connected. And treat any downed power line as live — the Red Cross says stay at least 35 feet (about 11 meters) from fallen lines and anything they touch, and call your emergency number.

When the power comes back

Start with food, because those decisions are concrete. Throw away anything exposed to temperatures of 40°F (4°C) or above for two hours or more, or with an unusual odor, color or texture. FoodSafety.gov's freezer rule is the mirror image: food may be safely refrozen if it still contains ice crystals or is at 40°F (4°C) or below, though the quality may suffer.

Two warnings deserve quoting rather than paraphrasing: never taste food to determine its safety, and when in doubt, throw it out. Something that looks and smells fine can still be unsafe — the criterion is temperature and time.

Medicines need a separate check. Ready.gov advises that if the power was out for more than a day, discard any medication that should be refrigerated — unless the label says otherwise — and contact your doctor or pharmacist immediately for a new supply. Ready.gov also says to ask your provider in advance how long medication can be stored at higher temperatures, and to get specific guidance for any medication that is critical for life. Do not discard one of those on a general rule — ask first.

Then restock. Ready.gov advises replacing expired items and rethinking your needs every year; the twice-yearly clock change is the easiest reminder. Write down what you ran out of — your first outage is the best audit you get for free.

The plan at a glance

An outage is an inconvenience rather than a disaster, provided it does not find you with an empty shelf and one flashlight full of dead batteries. Start with water and a carbon monoxide detector; the rest follows easily.