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Daylight harvesting in a school using enhanced skylights and an automatic-continuous dimming system

Conference ·
OSTI ID:361851
 [1]
  1. Arizona State Univ., Tempe, AZ (United States). Coll. of Architecture and Environmental Design

The hot-arid climate of Phoenix, Arizona and much of the Southwest region of the United States typically experiences 325 days a year with clear sky conditions. This provides a tremendous opportunity for illuminating buildings with daylighting and thus a great opportunity for reducing the use of electric lighting dramatically. To determine the energy savings and the costs associated with a ``daylight-harvesting`` system, an automatic continuous-dimming system consisting of dimmable electronic ballasts and photosensor was installed. The findings indicated that throughout the duration of the study, the dimming system reduced lighting energy consumption by approximately 75% during school hours. Thirty classrooms with (16) four-lamp troffers can each be equipped with dimming systems for about $15,000 more than the cost of equipping it with standard electronic ballasts. The system can save $4,900 a year and has a payback of three years. Over the life-cycle of the equipment (estimated at 15--20 years), the dimming system can save a school more than $85,000.

OSTI ID:
361851
Report Number(s):
CONF-970441--; ISBN 0-89553-212-3
Country of Publication:
United States
Language:
English