Estimation of Lighting Energy Savings From Atrium Daylighting for Office Buildings

Atria can offer several benefits to deep plan commercial and office buildings. This includes passive heating and cooling, ventilation, and daylighting. In order to use daylight effectively in atrium buildings, the characteristics that affect the light levels and distribution must be taken into account and analyzed. These elements include roofs, shapes, well geometries, surface finishes, and glazing types. The analysis outlined in this paper shows that a larger atrium area, higher window-to-wall ratio, clear windows, and a multi-story building provide the highest energy savings. The paper also presents a simplified calculation method to determine the percent lighting energy reduction attributed to atria in office buildings with continuous dimming. The lighting energy savings due to daylighting from atria can be up to 40%.