%0 Journal Article %J Energy and Buildings %D 2001 %T A Method for Simulating the Performance of Photosensor-Based Lighting Controls %A Charles K. Ehrlich %A Konstantinos M. Papamichael %A Judy Lai %A Kenneth L. Revzan %X

The unreliability of photosensor-based lighting controls continues to be a significant market barrier that prevents widespread acceptance of daylight dimming controls in commercial buildings. Energy savings from the use of daylighting in commercial buildings is best realized through the installation of reliable photoelectric lighting controls that dim electric lights when sufficient daylight is available to provide adequate background and/or task illumination. In prior work, the authors discussed the limitations of current simulation approaches and presented a robust method to simulate the performance of photosensor-based controls using an enhanced version of the radiance lighting simulation package. The method is based on the concept of multiplying two fisheye images: one generated from the angular sensitivity of the photosensor and the other from a 180 or 360 deg. fisheye image of the space as seen by the photosensor. This paper includes a description of the method, its validation and possible applications for designing, placing, calibrating and commissioning photosensor-based lighting controls.

%B Energy and Buildings %V 34 %P 883-889 %G eng %L LBNL-49018 %1

Windows and Daylighting Group

%2 LBNL-49018 %0 Conference Paper %B 2001 Building Simulation 7th International Building Performance Simulation Association Conference %D 2001 %T Simulating the Operation of Photosensor-Based Lighting Controls %A Charles K. Ehrlich %A Konstantinos M. Papamichael %A Judy Lai %A Kenneth L. Revzan %X

Energy savings from the use of daylighting in commercial buildings are realized through implementation of photoelectric lighting controls that dim electric lights when sufficient daylight is available to provide adequate workplane illumination. The dimming level of electric lighting is based on the signal of a photosensor. Current simulation approaches for such systems are based on the questionable assumption that the signal of the photosensor is proportional to the task illuminance. This paper presents a method that simulates the performance of photosensor controls considering the acceptance angle, angular sensitivity, placement of the photosensor within a space, and color correction filter. The method is based on the multiplication of two fisheye images: one generated from the angular sensitivity of the photosensor and the other from a 180- or 360-degree fisheye image of the space as seen by the photosensor. The paper includes a detailed description of the method and its implementation, example applications, and validation results based on comparison with measurements in an actual office space.

%B 2001 Building Simulation 7th International Building Performance Simulation Association Conference %C Rio de Janeiro, Brazil %8 08/2001 %G eng %L LBNL-47544 %1

Windows and Daylighting Group

%2 LBNL-47544