Know what your backup power will actually run.
Free calculators and plain-English guides for keeping the fridge cold, the sump pump running and the lights on when the grid goes down.
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Calculators
Enter your own numbers or start from typical values.
Can a power station run it?
Runtime tables, startup surge and practical tips for each appliance.
Can a power station run a refrigerator?Runtime by battery size, startup surge, and how long food stays safe.Can a power station run a sump pump?Startup surge, runtime in a storm, and when a dedicated backup pump is the better choice.Can a power station run a CPAP machine?Nights per charge with and without the humidifier, and why DC power lasts longer.Can a power station run a window air conditioner?Why AC drains batteries fast, what size works, and cheaper ways to stay cool.Can a power station run a space heater?Why electric heat drains batteries in minutes, and what to use instead.Can a power station run a chest freezer?One of the easiest loads for a battery, with runtimes of a day or more.Can a power station run a microwave?Why a 1,000 W microwave needs a 1,500 W power station, and how many minutes of cooking you get.Can a power station run a gas furnace?Blower wattage, runtime in cold weather, and the safe way to connect a hardwired furnace.Can a power station run a well pump?Why 240 V is the first hurdle, how big the startup surge is, and how much water a battery buys you.What size generator do you need to run a house?Running and starting watts for essentials, comfort and whole-home backup.How many solar panels to charge a power station?Calculator for panel watts and charging days, by battery size and sun hours.
How OutageReady works
The math is on the page
Every calculator shows its assumptions, and you can replace our typical values with the numbers on your own appliances.
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Safety over shortcuts
We explain how things work and send you to a licensed electrician for anything wired into your home.