In the CBCI EDGE curriculum, lighting efficiency is a critical strategy for reducing internal loads and lowering overall building energy consumption. Lighting efficacy is measured in lumens per watt, indicating how much visible light is produced for each unit of electrical power consumed. Among the listed options, light emitting diodes, or LEDs, provide the highest efficacy.

Typical performance ranges show that T8 and T5 fluorescent lamps are more efficient than older lighting technologies but generally deliver lower lumens per watt compared to modern LED systems. Compact fluorescent lamps are also more efficient than incandescent lighting but still fall short of the efficacy achieved by LEDs. Contemporary LED fixtures can exceed 100 lumens per watt and in many cases reach significantly higher values depending on product quality and design.

The EDGE software rewards high-efficiency lighting systems because reducing lighting power density directly lowers cooling loads in air-conditioned spaces and decreases total delivered energy consumption. LEDs also offer additional advantages such as longer lifespan and lower maintenance requirements, further supporting sustainable building design objectives. Therefore, among the listed options, LEDs have the highest efficacy and are the correct answer.