How to Use the Home Battery vs. Generator Cost Calculator
Enter the purchase price and expected replacement interval for each option, plus a generator's fuel price, consumption rate, and annual maintenance cost, then set how many hours a year you'd actually use backup power and how many years to compare — the calculator totals direct costs for each and shows which comes out cheaper.
Getting an accurate result depends mainly on entering a realistic hours-per-year figure, since that single input drives most of the difference between the two options.
Estimating your realistic hours of use
As covered in the cheaper-generator-costs-more guide, this is the single most impactful input — think through your area's realistic outage frequency and typical duration rather than guessing, since even a modest change in hours-per-year can shift which option comes out ahead.
Weighing the result alongside non-cost factors
As covered in the noise-and-fumes guide, treat the calculator's cost comparison as one input into the decision, not the only one — safety, noise, and where you can practically operate each option matter just as much for many households.