A novel idea for piping in sunlight where dreary fluorescent bulbs have long dominated.

Imagine if dull fluorescent lights could pump sunshine into your office instead. As this technology featured in Discover Magazine reports, researchers are doing that with fiber optics, promising office workers increased well-being and improved productivity.

In 2001, an estimated 25 percent of Americans suffered from Seasonal Affective Disorder. National Mental Health Association figures show. SAD, is a condition characterized by depression, lethargy, chronic fatigue and weight gain, among others symptoms, triggered by loss of sunlight.

Atop a three-story building at the east end of Oak Ridge National Laboratory in rural Tennessee, the warped image of researcher Jeff Muhs reflects off a silvery 46-inch-wide dish aimed at the afternoon sun. The slowly rotating mirror focuses sunlight into fiber-optic cables, which snake under the roof, past insulation and electrical wiring, and emerge in a light fixture one floor down. ?It?s real impressive . . . on a sunny day,? Muhs says sheepishly. On overcast days like today, a video demonstration has to suffice. Sunlight piped from the roof blends with fluorescent light in the fixture down below, offering a warm glow that looks much more natural than the harshness of conventional fluorescents.

Bringing the sun into the mix not only cuts electricity use for indoor illumination by up to 50 percent, it also addresses a fundamental problem with office buildings?how to get daylight into the interior. Architectural studies show that, at best, light from windows penetrates only about 20 feet inside a structure. The solution came to Muhs 10 years ago during a business trip to Japan. There he found silicone gel fibers that transmitted light far more efficiently than any he had seen before. He realized that a network of those fibers could spread sunshine throughout a building.

The idea was simple, but execution was a problem because passing clouds can suddenly dim the sun; on overcast days, of course, there?s no sunlight to tap into at all. Muhs eventually hit on a hybrid fixture that combines an acrylic sunlight-diffusing rod with two fluorescent lamps attached to a dimmer. He then added a sensor that can read the brightness of the room and adjust the fluorescents as needed.

Companies have reported that skylights and windows enhance worker productivity and sales, and some studies suggest that daylight raises students? test scores. A 1999 study of 108 stores in a retail chain found that outlets with skylights had 30 to 50 percent higher sales, even though most shoppers interviewed were unaware of the lights. They said the stores felt cleaner, more spacious, and brighter. Researchers at Rensselaer Polytechnic Institute are testing to see whether hybrid solar illumination similarly elevates productivity and mood.

Source: ScienCentral