The short answer
To prepare for a power outage: stock 1 gallon water per person per day (3-day minimum), 3-day non-perishable food + manual can opener, battery flashlights + spare batteries, 20,000+ mAh phone power bank, cooler with ice. If running a generator, place it 20+ feet from the house — never indoors. CO from generators kills 90+ Americans per year.
Power outages strike with little warning. Storms, ice events, transmission failures, ERCOT-style cold snaps — each year US households experience an average of 5-7 hours of outages, with regional outages running 24-72 hours after major storms. Preparation lives in three windows: before, during, after. This guide walks the 6-essential prep kit, the 4-hour fridge / 48-hour freezer food-safety rule, and the carbon-monoxide perimeter every backup system needs.
Before — build the kit
Battery-powered flashlight and headlamp, one per household member. Headlamp keeps both hands free. Spare batteries (AA + AAA) in a labeled bag.
Water: 1 gallon per person per day, 3-day minimum. Store in food-grade water containers. Rotate every 6 months.
Non-perishable food: 3-day supply. Canned soup, peanut butter, crackers, dried fruit, granola bars. Manual can opener (electric ones are useless during outage). Phone power bank: 20,000+ mAh, kept charged. Cooler + ice for fridge food during longer outages.
During — food safety and communications
Keep refrigerator and freezer doors closed. A full freezer holds safe temp for 48 hours; a half-full freezer for 24 hours. A refrigerator holds safe temp for 4 hours. Food above 40°F for 2+ hours must be discarded.
For longer outages: transfer fridge food to a cooler with ice. Buy block ice (lasts 18-36 hours) over cube ice (8-12 hours). For freezer items: leave the freezer closed; assess at the 48-hour mark.
Communications: phone power bank + battery radio. Most US utilities have outage-status websites or apps; smartphones with cell service can usually access them.
Generator carbon-monoxide safety perimeter
NEVER run a generator inside a house, garage, basement, crawl space, or partially enclosed area. Carbon monoxide is colorless, odorless, and lethal. The portable-generator-vs-battery-backup-safety guide covers backup options.
Place generator outside, 20+ feet from any window, door, or vent. The CO plume drifts downwind; if your house is downwind, increase distance to 30+ feet.
Connect appliances directly to the generator with rated extension cords. NEVER plug a generator into a wall outlet ("backfeeding") — this energizes the grid in your neighborhood and can kill utility workers.
- Generator: 20+ ft from house, never indoors.
- CO detectors on every floor (battery backup).
- Direct plug-in only — never backfeed wall outlets.
- Permanent installs require transfer switch + licensed electrician.
Recap
Bottom line
Power outage preparation is straightforward when broken into three windows: before (build the 6-essential prep kit), during (food-safety discipline plus communications), and after (assess and restock). Most US outages resolve inside 24 hours, but major storm events can run 72+ hours. Preparation matters most when it has to last more than 24 hours.
For households investing in backup power, the portable-generator-vs-battery-backup-safety guide compares the two main options. The 20-foot CO safety perimeter for generators is non-negotiable — CO from generators kills 90+ Americans per year, almost all preventable with proper placement. The solar-battery-backup-cost-payback guide covers battery economics for households also considering solar.
Want Seenra to run this for your account?
Forever free for households. Commercial accounts get a same-day quote with full commission disclosure. No credit pull, no on-site visit, no service interruption.
Get my fixed-rate quote →Common questions
Quick answers from the editorial desk
How long can my fridge stay cold during an outage?
What about my freezer?
How does Seenra make money on a household contract?
Sources
About the author
Harry ParkerEnergy Consultant, Seenra Inc
Energy Consultant at Seenra Inc. Harry advises US commercial buyers and households on supplier procurement, multi-site aggregation, and the operator-level math behind locked-rate contracts. Eight years on the buy side across PJM and ERCOT zones — he has run the load profile, the reverse auction, and the renewal calendar for portfolios from 50 kW restaurants to 18 MW manufacturing campuses.