Understanding Seasonal Variation
Solar production varies significantly by season. Understanding these patterns helps you set realistic expectations and optimize your system's performance year-round.
Summer (Peak Season)
Production
150-200%
of annual average
Why: Longer days, higher sun angle, more direct sunlight
Winter (Low Season)
Production
40-60%
of annual average
Why: Shorter days, lower sun angle, more clouds
Monthly Production Example
| Month | Production (kWh) | % of Annual Avg | Notes |
|---|---|---|---|
| June | ~75 kWh | 180% | Peak month |
| July | ~72 kWh | 170% | Peak month |
| May | ~65 kWh | 155% | High production |
| August | ~65 kWh | 155% | High production |
| April | ~50 kWh | 120% | Moderate |
| September | ~45 kWh | 110% | Moderate |
| March | ~35 kWh | 85% | Below average |
| October | ~30 kWh | 70% | Below average |
| November | ~20 kWh | 50% | Low |
| December | ~18 kWh | 45% | Lowest |
| January | ~20 kWh | 50% | Low |
| February | ~25 kWh | 60% | Low |
* Example: 800W system in Phoenix, AZ. Actual values vary by location.
Optimizing for All Seasons
Panel Angle
Adjustable mounts let you optimize angle seasonally. Steeper angle in winter, flatter in summer.
Keep Panels Clean
Snow, leaves, and dust reduce production. Regular cleaning is especially important in winter.
Monitor Production
Track monthly output to identify issues early. Sudden drops may indicate problems.
Size Appropriately
Size your system based on annual production, not peak summer output. Winter production is the limiting factor.
Pro Tip
Don't worry about low winter production - summer excess compensates. Calculate your annual production with our free calculator to see your year-round potential.