Daylight availability and models for global and diffuse horizontal illuminance and irradiance for Bangkok

We present results of a study on measurement of illuminance of daylight and solar irradiance from a station in the Asian Institute of Technology (AIT) campus, which is situated in a tropical region. Availability of daylight illuminance and solar irradiance on the horizontal and on vertical planes in cardinal directions is first presented. Mathematical models of global and horizontal daylight illuminance and solar irradiance are then presented. Our results reinforce earlier expectation of good potential for daylighting in tropical climate.