Solar Self-Sufficiency Calculator

Find on your bill — divide "Total Charges" by "Total kWh used".

Your city or postal code for better estimates (optional).

Approximate roof area available for solar panel installation.

The direction your roof faces (South is optimal in Northern Hemisphere).

The angle of your roof from horizontal (0 = flat, 90 = vertical).

Your ZIP/postal code for more accurate location-specific data.

The efficiency rating of solar panels you plan to use.

The power output rating of each solar panel.

Estimated system losses due to wiring, inverter, dirt, temperature, etc.

Expected annual increase in electricity prices.

Rate at which solar panels lose efficiency annually.

Expected operational lifespan of your solar panel system.

Average daily sunlight hours during winter months.

Average daily sunlight hours during summer months.

Estimated days per year with snow covering panels.

The basic structure of your roof affects panel placement options.

How complex is your roof design? More complex roofs may fit fewer panels.

Estimated cost per Watt for a fully installed system, including panels, inverter, and labor.

Total dollar amount of government rebates, tax credits, or other incentives available.

How your utility company charges for electricity.

Higher electricity rate during high-demand hours (typically afternoons/evenings).

Lower electricity rate during low-demand hours (typically nights/weekends).

How you plan to pay for your solar system.

Length of the loan term in years.

Annual interest rate for the loan.

The type of rebate program offered by your utility for excess solar production.

Total energy storage capacity of the battery system.

Round-trip efficiency (percentage of energy retained after storage).

Cost per kilowatt-hour of battery storage capacity.

When do you typically charge your electric vehicle?

Your estimated annual mileage for your electric vehicle.

Your electric vehicle battery capacity (check your vehicle specifications).