DAYLIGHTING AND ENERGY ANALYSIS FOR AIR-CONDITIONED OFFICE BUILDINGS

We propose a simple method for estimating the likely energy savings in electric lighting due to daylighting and the possible cooling penalty . Fractions of the working year and cooling season when daylighting al one is adequate to provide the indoor design illuminance are presented for on-off and top-up controls. Based on the simple average daylight factor method, energy savings in electric lighting have been estimated for a generic office building using measured outdoor illuminance data in Hong Kong. The daylight-induced cooling penalty is estimated using average solar heat gain factors. Our case study suggests that dayligh ting schemes can result in substantial energy savings in air-condition ed office buildings in Hong Kong. (C) 1998 Elsevier Science Ltd. All r ights reserved.