Solar Gap Analysis

Historical max consecutive "no-sun" days based on NASA POWER data (1984-2024).

How to use this tool:

1. Enter your latitude and longitude: You can enter multiple locations, one per line. Use either spaces or commas between the coordinates.
2. Enter your system loss percentage: (TOTAL Solar System Loss including: PV, inverter, cables, battery, etc.)
3. Enter your "no-sun" threshold (Wh/m²/day): This is the threshold below which a day is considered "no-sun" and the inverter will fail to function.
4. Click "Analyze Historical Gaps": The tool will fetch up to 40 years of daily data from NASA for each location provided.
5. View the results: The tool will show the longest consecutive "no-sun" gap found across all years for each location and the year it occurred. Copy this and paste into your spreadsheet.

The client report

• Get the max device power requirements (Wh/m²/day) (Name: DevWh)
  • This dictates the min size of the battery and the min W/h the PV must supply
• Get the min power produced by the PV system in your location (Wh/m²/day) (EC histogram)
  • The min power should include system losses
  • If you are running a split system (east/west), run the analysis for each azimuth separately and then take the minimum of the two.
• Get the max consecutive "no-sun" days in your location (Name: MaxGap)
  • Min battery size = MaxGap * DevWh