Renewable Off-Grid Energy System
Minimum System Size Calculator
How big should your Off-Grid system be?
If you are moving from a utility-connected home in the 'burbs to an off-grid home in the boonies, you will have the opportunity (perhaps necessity) of downsizing your electricity usage. In order to calculate how large your home power system needs to be, run the calculator below TWICE. Compare and adjust your plans according to your budget and lifestyle.
- Run it first with numbers from your current electricity usage.
- Then run it with figures from working through the Load Evaluation Worksheet, based on the energy efficient lighting and appliances you will choose for your new off-grid home.
For an approximate system cost please see our Off-Grid System Cost Guide
SUN HOURS/DAY ZONE MAP
How Many Sun Hours a Day Do You Get?
Zone 1 6 hours
Zone 2 5.5 hours
Zone 3 5 hours
Zone 4 4.5 hours
Zone 5 4.2 hours
Zone 6 3.5 hours
The hourly figure indicates the average (over the course of the year) amount of insolation (full sun hours) for these zones. These figures are based on the yearly average; consequently, systems based on these figures will provide more power in summer and less in winter. Winter figures for daily solar gain may be from 25% to 50% LESS than these average figures.
