| Title |
Study on the Luminous Efficacy of Daylight |
| Abstract |
Luminous efficacy relates two impotant quantities-daylight and solar radiation. Its use enables calculations of daylight availability and energy simulation in buildings to be integrated to a large extent. Luminous efficacy also enables daylight data to be generated where directly measured illuminances are not available. For the purpose of determining the luminous efficacy of solar radiation, an apparatus capable of simultaneously measuring exterior daylight illuminance and solar irradiance was installed on the top of the Suncheon National University building. The data collected during one year period are analized by a computer program. Horizontal and vertical luminous efficacies are evaluated as functions of solar altitude, sky condition, season and time of day. Based on sky measurements, values of luminous efficacy for total, diffuse and direct irradiance are presented. |