Solar elevation angle is the measure of the sun’s position relative to the observer’s horizon, expressed in degrees. When the sun is directly on the horizon, the elevation angle is zero; as the sun moves upward, the angle increases up to a maximum of 90 degrees when the sun is directly overhead. This angle is a critical parameter in solar energy applications, determining the intensity and angle of sunlight striking a particular location, thereby influencing solar panel efficiency and the design of solar thermal plants.
The solar elevation angle varies throughout the day and is affected by the observer’s geographic location and the day of the year. Near the equator, maximum solar elevation can reach or exceed 90 degrees, while locations closer to the poles experience lower maximum angles. Precise calculations of this angle require inputs of latitude, longitude, date, and time, often processed through algorithms such as the Solar Position Algorithm (SPA) which accounts for atmospheric refraction and Earth’s orbital variations.
Understanding and predicting the solar elevation angle is essential for various fields including meteorology, architecture, and agriculture. It assists in optimising crop planting orientations, designing buildings with natural light considerations, and setting up meteorological stations for accurate weather predictions. In photography and film, the angle influences lighting conditions and is vital for planning shoots during the golden hour or blue hour.
