Lighting accounts for 21% of the electricity used in the commercial sector. Offices are occupied mostly during daytime hours, and natural sunlight delivers a spectrum of light that’s most conducive to productivity and psychological well-being. It makes sense, therefore, to have as much natural lighting as possible available in offices. Unfortunately, not every office is located near a window, and even where windows are present, the apparent movement of the sun throughout the day means that a room may only have optimal sunlight for a few hours each day. The rest of the day is lit by fluorescent lights, which use electricity and produce a spectrum of light that’s inferior to natural daylight.