At what angle does the sun provide the most intense solar energy in a given location?

The sun provides the most intense solar energy at an angle of 90 degrees, which means it is directly overhead. When the sun's rays strike the Earth at this perpendicular angle, they are concentrated over a smaller surface area, leading to higher solar intensity. This phenomenon occurs in areas close to the equator during noon on certain days of the year when the sun's position reaches its zenith. During this time, shadows are the shortest, and solar energy is maximized, making it the ideal angle for heating and photosynthesis.

As the angle becomes less than 90 degrees, the solar energy is spread over a larger area, thus reducing its intensity. Therefore, the choice of 90 degrees accurately reflects the angle at which solar energy is most effectively concentrated and received on the Earth’s surface.