Evaluation of Effectiveness of LED Lighting in Buildings

Abstract

Solid-State Lighting (SSL) technologies including Light-Emitting Diodes (LEDs) have gained substantial attention because of their lower energy consumption over conventional lighting technologies. However, energy savings is only one aspect of effectiveness of LEDs. The quantity and quality of illumination together with the economic feasibility are also important in the determination of overall effectiveness. This study was carried out to evaluate all aspects of an installation of SSL, including energy savings, illumination quality, costeffectiveness, human performance and waste disposal. The study focused on a design that replaces fluorescent lamps (most commonly “T8” linear lamps) with LED products in a commercial building. The lighting level of the working plane at 00 degree of vertical angle was measured to be 370 lux ±12 for LED lamps and 144 lux ± 44 for fluorescent lamps. The lighting level of the 300 degree and 600 degree vertical angle were indicated as 365 lux for LED lamp and 100 lux for fluorescent lamp. This shows the lighting level of the LED is meeting with required standard (IESNA) which has given the range, 250-450 lux for a study area and an office environment. However, the florescent lighting was below the required level. The range of detected correlated colour temperature was 6000K – 6500K for both the lamps. In the associated survey among users of the space, more than 65% of the sample population provided a positive feedback on LED lighting system in relation to the human performance factors such as visibility, mood effect, visual health, colour appearance and work performance. Considering the above factors, LED lamps can be recommended as efficient and eco-friendly lighting systems for illumination of domestic and commercial buildings.