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Sun Peak Hours Calculator

Estimate peak sun hours for your location.

Sun Peak Hours Calculator

Estimate peak sun hours for your location

Formula

Based on latitude zone lookup

How to Use

  1. 1
    Enter your latitudeInput your latitude to estimate solar irradiance for your location.
  2. 2
    Select the monthChoose a specific month or view annual average.
  3. 3
    Review peak sun hoursSee estimated peak sun hours (PSH) per day for your location.
  4. 4
    Use for system sizingMultiply PSH × panel kW to estimate daily kWh production.

Frequently Asked Questions

What are peak sun hours?

Peak sun hours (PSH) represent hours of 1,000 W/m² solar irradiance. 5 PSH means total daily solar energy equals 5 hours at full sun intensity.

How many peak sun hours does my area get?

The US Southwest averages 6-7 PSH. The Northeast averages 3-4 PSH. Our calculator estimates based on your latitude and season.

Does cloudy weather reduce peak sun hours?

Yes, significantly. Overcast days may produce only 10-25% of clear-day irradiance. Annual averages already account for typical weather patterns.

How do peak sun hours affect solar panel sizing?

Fewer PSH means you need more panels. Example: 30 kWh/day ÷ 5 PSH = 6 kW system. With 4 PSH, you need a 7.5 kW system.