At this state planning yield, one 440 W panel corresponds to about 651 kWh/year before site-specific adjustments. Real output depends on roof orientation, tilt, shading, weather, inverter losses, equipment, soiling and local climate. Use ZIP-specific PVWatts for a better production estimate.
What this calculator tells you
The tool converts panel count and module wattage into DC system size, then multiplies that system size by a state-level planning yield. It shows estimated annual production plus simple monthly and daily averages.
For a one-panel estimate, choose the 1 panel preset. For a full array, enter the actual panel count from a proposal or from the Solar Panel Calculator.
Why real solar production changes by roof
- South-, east- and west-facing roof planes do not produce the same annual energy or the same hourly profile.
- Shade from trees, nearby buildings, chimneys or roof geometry can reduce output.
- Roof tilt, inverter clipping, wiring losses, soiling and equipment efficiency all matter.
- Weather varies from year to year even at the same address.
State solar yield is a planning estimate derived from NREL residential PV resource-class ranges, not a site-specific PVWatts result.
See the visual solar orientation guide for the difference between annual kWh and time-of-day production.
Move from state planning to your actual location
Use the Solar Production by State comparison to compare all 50 states. For a better estimate at your home, run the Home Solar Calculator with your ZIP code, which uses PVWatts production data. For roof-specific building insights, use the Solar Roof Analyzer.