Sunlight Calculator By Location

Solar Insolation Formula:

\[ I = I_0 \times \cos(\theta_z) \times \text{daylight hours} \]

Estimated Solar Insolation:

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1. What is Solar Insolation?

Solar insolation refers to the amount of solar radiation energy received on a given surface area during a specific time period. It is typically measured in kilowatt-hours per square meter per day (kWh/m²/day) and is crucial for solar energy system design and agricultural planning.

2. How Does the Calculator Work?

The calculator uses the solar insolation formula:

\[ I = I_0 \times \cos(\theta_z) \times \text{daylight hours} \]

Where:

\( I \) — Solar insolation (kWh/m²/day)
\( I_0 \) — Solar constant (1.367 kW/m²)
\( \theta_z \) — Solar zenith angle (degrees)
daylight hours — Duration of sunlight exposure

Explanation: The calculation considers latitude, date, solar declination, and daylight hours to estimate daily solar radiation received at Earth's surface.

3. Importance of Solar Insolation Calculation

Details: Accurate solar insolation data is essential for solar panel system sizing, agricultural crop planning, building design for energy efficiency, and climate studies.

4. Using the Calculator

Tips: Enter latitude in degrees (-90 to +90, negative for Southern Hemisphere), and select the desired date. The calculator will estimate daily solar radiation for that location and date.

5. Frequently Asked Questions (FAQ)

Q1: What factors affect solar insolation?
A: Latitude, time of year, atmospheric conditions, cloud cover, and elevation all significantly impact solar radiation levels.

Q2: How accurate is this calculator?
A: This provides theoretical maximum values. Actual insolation may be lower due to weather conditions, atmospheric absorption, and local topography.

Q3: What is the solar constant?
A: The solar constant is the amount of solar electromagnetic radiation received at the top of Earth's atmosphere, approximately 1.367 kW/m².

Q4: Why does latitude affect solar insolation?
A: Higher latitudes receive sunlight at more oblique angles, spreading the same amount of energy over larger surface areas, reducing intensity.

Q5: How does season affect solar insolation?
A: Earth's axial tilt causes seasonal variations in solar angle and daylight duration, significantly affecting daily insolation levels.