To get through 72 hours without grid power, you need three things: a list of what must stay on, enough fuel or battery to run it in short sessions, and a clock for your food. A closed refrigerator keeps food safe for about 4 hours and a full freezer for about 48, so those two numbers set your whole schedule.
A short outage is an annoyance. A three-day outage is different. Phones die, food warms up, the house gets cold or hot, and the gas stations nearby may have no power to pump fuel.
This checklist turns those three days into a plan you can follow by the hour. You will work out a simple power budget, see how much fuel 72 hours really takes, learn the food safety limits, and get a timeline from the first minute to the last. The safety rules come from Ready.gov, the Food and Drug Administration and the Centers for Disease Control and Prevention. We have not tested the products named here.
Your 72-hour emergency power plan
Three days, three clocks to watch
Food safety times are from the FDA. Supply guidance is from Ready.gov. Product details come from current Amazon listings, checked in October 2026.
Quick answer
Before an outage, list your must-run loads, test your generator or charge your power station, and store stabilized fuel. When the power fails, keep the refrigerator and freezer shut and note the time. Run the generator in short sessions, outdoors and at least 20 feet from the house, to cool the refrigerator and charge your devices. Plan about 11 to 14 gallons of gasoline for three days with a 5,000-watt generator run six hours a day. Throw out refrigerated food that has been above 40 °F for four hours or more.
How we put this checklist together
We have not tested these products. Food safety times come from the U.S. Food and Drug Administration. Supply and generator guidance comes from Ready.gov, and carbon monoxide facts come from the Centers for Disease Control and Prevention. Appliance wattages are typical figures from Champion Power Equipment’s chart. The power budget and fuel arithmetic are our own examples, and we show the working.
In this guide
- Why Plan for 72 Hours?
- Step 1: List What Must Stay On
- Step 2: Work Out Your Power Budget
- Step 3: Turn the Budget Into Fuel
- The 72-Hour Timeline: What to Do and When
- Food Safety: The Rules That Set Your Schedule
- Generator Safety for a Long Outage
- No Generator? A Battery-Only Plan
- Gear Worth Having Before the Storm
- Water, Heat and Staying in Touch
- After the Power Returns
- Common 72-Hour Mistakes (and the Fix)
- Pro Tips for a Calmer Three Days
- Real-Life Scenarios: Three Homes, Three Plans
- Emergency Power 72-Hour Checklist: FAQ
- Your 72-Hour Emergency Power Checklist
Why Plan for 72 Hours?
Most outages end in a few hours. The ones that hurt last days. They usually follow a storm, when roads are blocked, stores are shut and everyone nearby wants the same fuel and ice.
Ready.gov tells households to keep water and non-perishable food for several days. Three days, or 72 hours, is a common target to plan around. It is long enough to cover most storm outages and short enough to prepare for without filling the garage.
The mistake most people make is treating day one like any other evening. They open the refrigerator, run the generator all night and burn a third of their fuel before bedtime. A 72-hour plan is really a plan to ration.
Key insight: you do not need power all the time. You need it at the right times. Short, planned sessions make three days of fuel out of one day of careless running.
Step 1: List What Must Stay On
Walk through the house and sort everything into three groups. Be strict. Every extra load costs fuel.
| Group | Examples | Plan |
|---|---|---|
| Must run | Refrigerator, freezer, furnace fan, well or sump pump, medical equipment | Power these first, in sessions |
| Should run | Phone and laptop charging, router, a few LED lights, radio | Small loads. Run from a battery if you can |
| Can wait | Oven, dryer, dishwasher, central air, electric water heater | Leave these off for three days |
Now write the wattage beside each must-run item. The label on the appliance is the best source. If you cannot find it, these typical figures help.
| Appliance | Running watts | Starting watts |
|---|---|---|
| Refrigerator | 150 to 400 | 800 to 1,200 |
| Furnace fan, 1/2 hp | 300 to 800 | 800 to 1,600 |
| Sump pump, 1/2 hp | 800 to 1,050 | 1,300 to 2,150 |
| Well pump, 1/2 hp | 750 to 1,000 | 1,500 to 2,000 |
| Microwave | 600 to 1,200 | Same as running |
Our free Emergency Power Planner builds this list for you, and what size generator do I need explains how to turn it into a generator size.
Step 2: Work Out Your Power Budget
Watts tell you how big a generator you need. Watt-hours tell you how much energy you will use in a day. That is the number that decides your fuel and battery.
The sum is easy: watts multiplied by hours.
Here is an example for a home in winter. The hours are assumptions for the example, so change them to match your own home.
| Load | Watts | Hours per day | Watt-hours per day |
|---|---|---|---|
| Refrigerator, compressor running | 300 | 8 | 2,400 |
| Furnace fan | 500 | 8 | 4,000 |
| LED lights | 60 | 5 | 300 |
| Router and phone charging | 30 | 24 | 720 |
| Total | 7,420 |
That is about 7.4 kilowatt-hours a day. Take away the furnace in mild weather and it falls to about 3.4.
Two lessons come out of this table.
- Motors use most of the energy. Lights and phones are almost nothing beside a furnace fan.
- Small loads suit batteries. The router, lights and phones use about 1,000 watt-hours a day, which is what one mid-size power station holds.
Step 3: Turn the Budget Into Fuel
A generator does not sip fuel in exact step with your load. It burns a base amount whenever it runs. So the way to save fuel is to run it for fewer hours and load it well while it runs.
A good pattern is three sessions of about two hours each: morning, afternoon and evening. In each session the refrigerator and freezer get cold again, the furnace warms the house, and every battery gets charged.
| Generator size | Fuel per hour at half load | Hours in 3 days | Fuel for 72 hours |
|---|---|---|---|
| 3,500 watts | 0.3 to 0.4 gallons | 18 | About 5.5 to 7 gallons |
| 5,000 watts | 0.6 to 0.75 gallons | 18 | About 11 to 14 gallons |
| 7,500 watts | 0.9 to 1.1 gallons | 18 | About 16 to 20 gallons |
Run the same generators around the clock and you would need four times as much.
Add a margin. Cold weather, a bigger load or a fourth day will all eat into your stock. Check what your local fire code allows you to store, and keep gasoline in approved containers. How much gas a generator uses has the full tables.
Tip: fuel that waits must be treated
Gasoline goes stale. If your cans sit for months, add a stabilizer when you fill them and rotate the fuel through your car each season. Our guide on how long gasoline lasts explains the limits.
The 72-Hour Timeline: What to Do and When
Print this section. In an outage you will not want to think. You will want to follow.
Hour 0 to 1: Make it safe
- Check that it is a real outage. Look at your breakers, then at the neighbors’ lights.
- Report it to your utility and note the time the power failed.
- Get out flashlights and lanterns. Leave the candles in the drawer.
- Unplug sensitive electronics such as computers and televisions.
- Leave one lamp switched on so you know when the power returns.
- Keep the refrigerator and freezer closed. The four-hour clock has started.
Hour 1 to 4: Set up, do not rush
- Decide where the generator will sit. Outdoors, at least 20 feet from doors, windows and attached garages, with the exhaust pointing away.
- Test your carbon monoxide alarms. They should have working batteries.
- Lay out your cords before dark.
- Put phones into low-power mode and start using power banks.
- Hold off on starting the generator unless you need heat or a pump. The refrigerator is still fine.
Hour 4: The first decision point
A closed refrigerator stays cold for about four hours. So before that time is up, do one of these.
- Run a generator session of an hour or two to bring the refrigerator and freezer back down.
- Move the most perishable food to a cooler packed with ice.
- Cook and eat what will not keep.
Hour 4 to 24: Settle into sessions
| Session | When | What to run |
|---|---|---|
| Morning | About 2 hours | Refrigerator, freezer, furnace fan, well pump, coffee maker, all chargers |
| Afternoon | About 2 hours | Refrigerator, freezer, a microwave meal, chargers |
| Evening | About 2 hours | Refrigerator, freezer, furnace fan, lights, chargers |
| Overnight | Off | Battery lights and a power station for small loads |
At each session, check the fuel and the oil. Stop the engine and let it cool before you refuel.
Hour 24 to 48: The freezer clock
A freezer that is half full keeps its temperature for about 24 hours. A full one lasts about 48. If you have been running sessions, your freezer is fine. If you have no generator, this is the day to act.
- Group frozen food together so it keeps itself cold.
- Add dry ice if you can get it. The FDA says fifty pounds should keep a fully stocked 18-cubic-foot freezer cold for two days.
- Count your fuel. You should have about two-thirds left at hour 24.
- Check on neighbors, most of all anyone elderly or living alone.
Hour 48 to 72: Hold steady and check everything
- Read the thermometers in the refrigerator and freezer before you eat anything from them.
- Check the generator’s oil at every refuel, as the manual directs.
- Refill water containers if the supply is still safe.
- Listen to a battery or crank radio for restoration news.
- Plan for day four. If fuel is short, cut to two sessions.
Food Safety: The Rules That Set Your Schedule
These limits come straight from the Food and Drug Administration. Tape them to the refrigerator door.
| Situation | Limit | What to do |
|---|---|---|
| Refrigerator, door kept shut | About 4 hours | Run a session or move food to a cooler before then |
| Full freezer, door kept shut | About 48 hours | Keep it closed and group the food together |
| Half-full freezer | About 24 hours | Act a day sooner |
| Refrigerated food above 40 °F for 4 hours or more | Unsafe | Throw it out |
| Food left at room temperature | 2 hours, or 1 hour above 90 °F | Throw it out |
| Frozen food still at 40 °F or below | Safe | It may be refrozen |
The FDA also says to keep appliance thermometers in both the refrigerator and the freezer. The refrigerator should be at or below 40 °F and the freezer at or below 0 °F. Without a thermometer you are guessing, and guessing with food is how people get sick.
Never taste food to decide if it is safe. When in doubt, throw it out.
Generator Safety for a Long Outage
Three days of running means three days of chances to make a mistake. Tired people make them.
Carbon monoxide is the real danger
Every year in the United States, more than 400 people die from accidental carbon monoxide poisoning not linked to fires, according to the Centers for Disease Control and Prevention. Use generators outside only, more than 20 feet from any window, door or vent. Never run one in a garage, a basement or a shed, even with the door open. Symptoms include headache, dizziness, weakness, upset stomach, vomiting, chest pain and confusion. If anyone feels unwell, get into fresh air and call 911.
- Use heavy outdoor cords. Ready.gov says to connect the generator to appliances with heavy-duty extension cords.
- Never plug a generator into a wall outlet. It can send power into the utility lines. See how to connect a generator without a transfer switch for the safe options.
- Refuel with the engine off and cool.
- Keep it dry, but never by moving it under a roof attached to the house.
- Secure it at night when you shut it down.
Our generator safety tips cover all of this in detail.
No Generator? A Battery-Only Plan
You can still get through 72 hours. You just have to be stricter.
| Tool | Good for | Not enough for |
|---|---|---|
| Power banks | Phones for a day or two | Anything with a motor |
| Rechargeable lanterns | Light every evening | Heat or cooling |
| Portable power station | Router, lights, phones, a CPAP machine | Running a refrigerator for three days |
| Your car | Charging phones while parked outdoors | Powering the house |
A mid-size power station stores about 1,000 watt-hours. That covers the “should run” group in our example for roughly a day. To last three days, you need a way to recharge it, such as a solar panel, or you need to cut the loads to phones and lights only.
For food, lean on ice, coolers and the 48-hour freezer window. Eat the refrigerated food first, then the frozen food as it thaws, then your shelf-stable supplies.
If you charge phones from a car, park it outdoors. Never run a vehicle in a garage, even with the door open.
Gear Worth Having Before the Storm
Each of these had an active Amazon listing with an Add to Cart button when we checked in October 2026.
Buy this first
Kidde Carbon Monoxide Detector with 10-Year Battery and Digital Display (C3010D)
A battery-powered carbon monoxide alarm that keeps working through an outage. It needs no wiring.
- Power10-year sealed lithium battery
- SensorElectrochemical
- Alarm85 decibels
- DisplayDigital, updates every 15 seconds
- MemoryPeak Level Memory
- Warranty10-year limited
- Why it works: it has its own battery, so losing grid power does not switch it off.
- Who it is best for: every home that owns a generator, a gas heater or a fireplace.
- What it solves: a gas you cannot see or smell. The display shows a number, not just a warning.
- Handy extras: it can hang on a wall or stand on a table, so you can put it near the bedrooms.
- Keep in mind: an alarm is a backup. The generator still belongs outdoors, 20 feet from the house.
As an Amazon Associate we earn from qualifying purchases. Specs come from the Amazon listing, checked October 2026.
Takes the guesswork out of food
TempPro TempAir Refrigerator and Freezer Thermometer, 2 Pack
Two small digital thermometers, one for the refrigerator and one for the freezer. They tell you whether food has stayed in the safe range.
- Quantity2 thermometers
- Range-4 °F to 122 °F
- AccuracyWithin 1.8 °F
- DisplayLarge backlit LCD
- Water ratingIPX6
- Battery coverOpens with a coin
- Why it works: the FDA limits are based on temperature, so a reading beats a guess.
- Who it is best for: anyone with a full freezer that would be costly to lose.
- What it solves: the “is this still good?” question at hour 30.
- Handy extras: the backlight makes it readable inside a dark freezer.
- Keep in mind: you still have to open the door to read it, so check quickly and only when you need to.
As an Amazon Associate we earn from qualifying purchases. Specs come from the Amazon listing, checked October 2026.
Keeps stored fuel usable
STA-BIL Storage Fuel Stabilizer, 32 oz
A gasoline additive for fuel that will sit in cans or in a generator tank between storms.
- Size32 oz
- TreatsUp to 80 gallons
- Dose1 oz per 2.5 gallons
- Storage lifeUp to 24 months, as listed
- FuelsEthanol and non-ethanol gasoline
- UseAdd before filling the can
- Why it works: treated fuel is far more likely to start an engine after months in storage.
- Who it is best for: anyone who keeps gasoline for a generator.
- What it solves: stale fuel, which is a very common reason a generator will not start after storage.
- Handy to know: after adding it to a generator tank, run the engine for a few minutes so treated fuel reaches the carburetor.
- Keep in mind: it slows fuel aging. It cannot rescue gasoline that has already gone bad.
As an Amazon Associate we earn from qualifying purchases. Specs come from the Amazon listing, checked October 2026.
Silent power for small loads
Jackery Explorer 1000 v2 Portable Power Station (1,070 Wh, 1,500 W)
A battery power station with no engine and no exhaust. It can be used indoors, overnight, when a generator must stay off.
- Capacity1,070 Wh
- AC output1,500 W
- Surge3,000 W
- BatteryLFP, 4,000 cycles to 70%
- Weight23.8 lb
- RechargeAbout 1.7 hours by default
- Why it works: it covers the small loads silently, so the generator can rest at night.
- Who it is best for: households with a router, phones, lights or a CPAP machine to keep going.
- What it solves: the overnight gap. You do not have to choose between noise and darkness.
- Handy to know: recharge it during each generator session and it will be full again by evening.
- Keep in mind: about 1,000 watt-hours will not run a refrigerator for three days. A solar panel is not included.
As an Amazon Associate we earn from qualifying purchases. Specs come from the Amazon listing, checked October 2026.
Smaller items round out the kit: a crank and battery weather radio such as the Midland ER310, a rechargeable lantern such as the Lepro 1000-lumen lantern, a 20,000 mAh Anker power bank for phones, and a heavy Southwire 12-gauge outdoor extension cord.
Water, Heat and Staying in Touch
Power is only part of the plan. Ready.gov’s basic kit covers the rest.
- Water: one gallon per person per day for several days, for drinking and sanitation.
- Food: a several-day supply that needs no refrigeration, plus a manual can opener.
- News: a battery-powered or hand-crank radio and a NOAA Weather Radio with tone alert.
- Light: flashlights and extra batteries.
- Phones: chargers and a backup battery.
- First aid kit and any medicines you need.
In the cold, close off unused rooms, gather in one space and dress in layers. Never heat a home with a gas oven, a grill or a camp stove.
In the heat, stay on the lowest floor, keep blinds shut and drink plenty of water.
If someone depends on powered medical equipment, talk to the doctor and the equipment supplier now about battery backup, and tell your utility. Do not wait for the outage.
After the Power Returns
- Switch the house back to utility power before you stop the generator, if you use a transfer switch or interlock.
- Let the generator cool, then refuel it and check the oil.
- Change the oil if it ran for several days. Check the air filter.
- Check food temperatures and throw away anything doubtful.
- Restock fuel, batteries, water and food while the stores are quiet.
- Write down what went wrong. Fix it before the next storm.
The generator maintenance checklist and how to store a generator cover what to do next.
Common 72-Hour Mistakes (and the Fix)
Pro Tips for a Calmer Three Days
- Write the outage time on a sticky note and put it on the refrigerator.
- Freeze water bottles now. They keep the freezer cold longer and give you drinking water later.
- Charge everything during each session. Phones, power banks, lanterns and the power station.
- Cook in batches while the generator is running.
- Keep cash in the house. Card readers stop when the power does.
- Fill the car’s tank before a storm is due.
- Print this checklist. Your phone may be the first thing to run flat.
Real-Life Scenarios: Three Homes, Three Plans
These are typical situations that people describe in forums and reviews. They are examples to help you plan, not quotes from real people.
🏢 The apartment household
No generator is allowed. Outages are rare but can last a day or two.
You need light, charged phones, a radio and a food plan built around ice.
Best fit: power banks, lanterns and a power station
🏠 The suburban home
A 5,000-watt portable generator sits in the garage with one can of fuel.
You need about 11 to 14 gallons, a session plan and a carbon monoxide alarm.
Best fit: three two-hour sessions a day
🚰 The rural home on a well
No power means no water, and the nearest gas station is far away.
You need a 240-volt generator, more stored fuel and stored water.
Best fit: a larger generator, a proper hookup and a wider margin
Emergency Power 72-Hour Checklist: FAQ
How much fuel do I need for a 72-hour power outage?
It depends on the generator and how long you run it. A 5,000-watt generator at half load uses about 0.6 to 0.75 gallons an hour, so six hours a day for three days takes about 11 to 14 gallons. Add a margin.
How long will food last in the refrigerator without power?
The FDA says a refrigerator keeps food cold for about 4 hours if it is unopened. A full freezer holds its temperature for about 48 hours, or about 24 hours if it is half full.
Should I run my generator all night during an outage?
Usually not. A closed refrigerator and freezer hold their temperature for hours, so most homes can shut the generator down overnight and save fuel. Use battery lights and a power station for small loads.
How far should a generator be from the house?
At least 20 feet from doors, windows and attached garages, outdoors, with the exhaust pointing away. Never run it in a garage, basement or shed.
Can a portable power station get me through three days?
It can cover phones, lights, a router and similar small loads if you ration it or recharge it. About 1,000 watt-hours will not run a refrigerator for three days.
When should I throw food away after an outage?
Throw out refrigerated perishable food that has been above 40 °F for 4 hours or more. Frozen food that is still at 40 °F or below is safe and may be refrozen.
Your 72-Hour Emergency Power Checklist
- List the loads that must run and write down their watts.
- Work out your daily watt-hours.
- Store enough stabilized fuel for three days of sessions, plus a margin.
- Test the generator under load, or charge the power station.
- Fit battery-powered carbon monoxide alarms and test them.
- Put thermometers in the refrigerator and the freezer.
- Pick the generator’s spot, 20 feet from the house.
- Keep heavy outdoor cords with the generator.
- Store one gallon of water per person per day.
- Stock food that needs no cooking, and a manual can opener.
- Charge power banks, lanterns and a radio.
- Print this plan and keep it with the flashlights.
The bottom line
Three days without power is manageable when you ration on purpose. Know your must-run loads, run the generator in short sessions, watch the food clocks and keep the engine outdoors. Do the sums and buy the fuel before the forecast turns bad.
As an Amazon Associate we earn from qualifying purchases.
Sources: U.S. Food and Drug Administration, “Food and Water Safety During Power Outages and Floods”; Ready.gov, “Build a Kit” and “Power Outages”; Centers for Disease Control and Prevention, carbon monoxide poisoning basics; Champion Power Equipment’s published wattage chart; current Amazon listings for the Kidde, TempPro, STA-BIL, Jackery, Midland, Lepro, Anker and Southwire products named in this guide. All checked October 2026.
