Accurately determine the sun’s position relative to your location using our advanced sunlight angle calculator. This tool helps engineers, architects, and solar enthusiasts calculate the Solar Altitude Angle to optimize solar panel placement and building shade designs.
Sunlight Angle Calculator
Sunlight Angle Calculator Formula
Variables:
- α (Alpha): Solar Altitude Angle (The result).
- φ (Phi): Your Latitude (positive for North, negative for South).
- δ (Delta): Solar Declination (changes based on the day of the year).
- h (Hour Angle): Distance from solar noon (15° per hour).
What is a Sunlight Angle Calculator?
A sunlight angle calculator (also known as a solar altitude calculator) determines the vertical angle of the sun relative to the horizon at a specific location, date, and time. This angle is 0° at sunrise/sunset and reaches its peak at solar noon.
Understanding this angle is critical for maximizing solar energy harvest, as the intensity of light hitting a surface is directly proportional to the sine of the angle of incidence. Architects also use these values to design eaves and overhangs that block summer sun while allowing winter warmth.
How to Calculate Sunlight Angle (Example)
Let’s calculate the angle for Los Angeles (Lat: 34°) on the Summer Solstice (Day 172) at Solar Noon (12:00):
- Step 1: Calculate Declination (δ). For day 172, δ ≈ +23.45°.
- Step 2: Calculate Hour Angle (h). At noon, h = 0°.
- Step 3: Apply formula: sin(α) = sin(34)sin(23.45) + cos(34)cos(23.45)cos(0).
- Step 4: Result: α ≈ 79.45°. The sun is high in the sky.
Frequently Asked Questions (FAQ)
Generally, locations closer to the equator experience higher sun angles year-round, while polar regions experience lower angles and extreme seasonal variance.
Is Solar Time different from Clock Time?Yes. Solar time is based on the sun’s position (noon is exactly when the sun is highest), while clock time is standardized by time zones and may include Daylight Savings adjustments.
Why is the sunlight angle important for solar panels?Solar panels perform best when sunlight hits them at a 90° angle. Knowing the sun’s path allows you to tilt your panels to minimize the “cosine loss.”
What is the Zenith Angle?The Zenith angle is simply 90° minus the Altitude angle. it represents the angle between the sun and the vertical line directly above you.