1. What is the Solar Altitude Angle?

The solar altitude angle (α) is the angle between the sun's rays and the horizontal plane. It varies throughout the day and depends on the observer's latitude, the sun's declination, and the hour angle.

2. How Does the Calculator Work?

The calculator uses the solar altitude angle equation:

Where:

• \( \alpha \) — Solar altitude angle (degrees)
• \( \phi \) — Latitude (degrees, positive north)
• \( \delta \) — Solar declination (degrees, ±23.5° max)
• \( H \) — Hour angle (degrees, 0° at solar noon)

Explanation: The equation calculates the sun's elevation above the horizon at a specific location and time.

3. Importance of Solar Angle Calculation

Details: Solar altitude angle is crucial for solar panel positioning, daylighting design, photography planning, and understanding solar radiation intensity.

4. Using the Calculator

Tips: Enter latitude (-90° to 90°), declination (-23.5° to 23.5°), and hour angle (-180° to 180°). All values must be valid within these ranges.

5. Frequently Asked Questions (FAQ)

Q1: What is solar declination?
A: The angle between the sun's rays and the Earth's equatorial plane, varying between ±23.5° throughout the year.

Q2: How is hour angle calculated?
A: 15° per hour from solar noon (e.g., 10 AM = -30°, 2 PM = +30°).

Q3: What's a typical solar altitude at noon?
A: At equinox, equals 90° minus latitude. At solstice, add/subtract 23.5° depending on season.

Q4: When is the sun directly overhead?
A: Only between the Tropics (23.5°N to 23.5°S) when declination equals latitude and hour angle is 0°.

Q5: How does this relate to solar azimuth?
A: Azimuth (compass direction) can be calculated once altitude is known using additional formulas.