Analytic Representation of Relation between Solar Altitude Angle and Local Time for Calculating Daylight Irradiance and Illuminance of the Earth Surface

Abstract

The analytic expression which sets relation between the solar altitude angle and local time at a random point of the Earth surface on a random day of a year is obtained. The obtained expression and derived relations allow one to conduct calculations of daylight irradiance and illuminance of the Earth surface in analytic form.