Which of the following is most associated with lighting energy savings?

The association of lighting energy savings with efficacy is rooted in the definition of efficacy itself, which refers to the amount of light produced (measured in lumens) per unit of energy consumed (measured in watts). Higher efficacy means that a lighting system can produce more light for less energy, leading to significant energy savings. For instance, LED lights typically have a higher efficacy compared to traditional incandescent bulbs, meaning they provide more light output while using less electricity.

This focus on efficacious lighting directly correlates to reducing overall energy consumption, making it a critical factor in energy savings initiatives. Proper selection of lighting with high efficacy can result in lower utility bills and reduced environmental impact, aligning with sustainable building practices.

Illuminance pertains more to the intensity of light on a surface, which does not necessarily indicate how efficiently energy is being used. Distribution refers to how evenly light is spread across a space, while the frequency of use addresses how often lighting is activated but does not directly affect the efficiency of the lighting source itself. Thus, efficacy stands out as the most prominent factor when considering energy savings related to lighting.