How Much Backup Power Do I Need?

A simple framework for estimating essential loads, watts and runtime.

Define essential loads

During an outage, most homes do not need every circuit. Refrigeration, communications, selected lighting, medical or work needs and climate-related essentials should be prioritized according to your situation.

Match technology to runtime

Batteries are quiet and convenient but have finite stored energy. Fuel generators can run longer with fuel but add exhaust, noise and maintenance. Solar can recharge batteries when conditions and system size permit.

Where to go next

Continue with our home energy independence guide, compare backup power options, or read our Power Efficiency Guide review if you are evaluating that DIY offer.