Solar Peak Sun Hours Calculator

Convert daily solar irradiation into equivalent peak sun hours.

About Solar Peak Sun Hours Calculator

Because peak irradiance is defined as 1 kW/m², daily irradiation in kWh/m² is numerically the same as peak sun hours. That identity is what makes the unit so convenient for sizing. Peak sun hours vary from about 2.5 in northern Europe to over 6 in desert regions, which is the single largest determinant of solar output.

Formula

Solar Peak Sun Hours

Peak sun hours equal daily irradiation in kWh/m², since peak irradiance is 1 kW/m²

peak sun hours: Numerically identical to daily kWh/m² of irradiation

Worked example

With the default values below, Solar Peak Sun Hours Calculator returns Peak Sun Hours of 3.500. Change any input above and every figure here is recalculated in your browser.

Inputs used

Daily solar irradiationminimum 0 kWh/m2: 3.5 kWh/m2
System sizeminimum 0 kW: 5 kW
System lossesaccepts 0–100 %: 18 %

Results

Peak Sun Hours: 3.500 h
Daily Generation: 14.350 kWh
Annual Generation: 5,237.8 kWh
Specific Yield: 1,047.6 kWh/kW
Monthly Generation: 436.48 kWh

Step by step

1Values used
2Solar Peak Sun Hours
3Peak Sun Hours= 3.500 h
4Daily Generation= 14.350 kWh
5Annual Generation= 5,237.8 kWh
6Specific Yield= 1,047.6 kWh/kW
7Monthly Generation= 436.48 kWh

Assumptions and limits

The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 3 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

How is Solar Peak Sun Hours calculated?

Peak sun hours equal daily irradiation in kWh/m², since peak irradiance is 1 kW/m² Because peak irradiance is defined as 1 kW/m², daily irradiation in kWh/m² is numerically the same as peak sun hours. That identity is what makes the unit so convenient for sizing.

Why does Solar Peak Sun Hours matter?

Peak sun hours vary from about 2.5 in northern Europe to over 6 in desert regions, which is the single largest determinant of solar output.

What values do I need to enter?

This calculator takes 3 inputs: Daily solar irradiation, System size, System losses. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.