Energy-efficient lighting in Thai commercial buildings

Abstract

We explore the opportunities to reduce the electricity required for lighting in prototypical Thai offices, hotels, and shopping centers. Using a whole-building energy analysis approach, we calculate the savings from lighting conservation measures directly, and from associated reductions in cooling load. Ancillary cost savings of air-conditioning energy and capacity comprise a significant 30 to 50% of the total. Lighting technologies considered in this study include electronic ballasts; tri-phosphor, narrow-diameter lamps; specular reflectors; occupancy sensors; lumen maintenance and daylighting controls; and compact fluorescent lamps. From a societal economic perspective, the cost of conserved energy of employing all applicable lighting conservation measures to these buildings is one-quarter or less than the average retail price of electricity for commercial customers, with a payback time of less than one year in hotels and retail buildings and approximately three years in offices. The internal rate of return for installing all lighting measures is 35% in offices, 142% for hotels, and 107% for shopping centers. Several current policy initiatives in Thailand, including a proposed energy standard for commercial buildings, with specific provisions for lighting, and plans by the nation's electric utility to develop two commercial sector conservation programs, should help to spur the adoption of more efficient lighting products. We strongly recommend that the currently high tariffs and taxes (50% and greater) for imported efficient lighting products be reduced.