Generators Generator for a Fridge: What Size Do You Actually Need?By Barret AbramowJune 23, 20260 Most standard refrigerators require a 2,000-2,400W generator for fridge-only backup. Add a freezer and step up to 3,500W to 4,500W. Add an air conditioner, and you need 6,500W or more. Keep reading for the full sizing breakdown.