Which concept maximizes occupant health and comfort by using natural lighting to reduce energy consumption and stress on the eyes?

• A. Occupancy sensors
• B. Task tuning
• C. Dimming
• D. Daylight harvesting

Answer: (D)

Daylight harvesting centers on using natural daylight to illuminate a space and automatically adjust artificial lighting to maintain comfortable, consistent levels. This approach supports occupant health and comfort because natural light helps regulate circadian rhythms, reduces eye strain, and provides a more pleasant visual environment compared to constant or harsh artificial lighting. At the same time, it reduces energy use by dimming or turning off electric lights when there’s enough daylight available, guided by sensors that monitor ambient light.

The other ideas focus on energy savings or task needs without specifically leveraging daylight. Occupancy sensors save energy by turning lights on only when spaces are used. Dimming reduces artificial light levels but doesn’t inherently rely on daylight to meet lighting needs. Task tuning adjusts lighting to suit particular activities but doesn’t specifically optimize natural light as a primary source. Daylight harvesting uniquely combines health, comfort, and energy efficiency by integrating natural light with controlled artificial lighting.