There’s just nothing like a sunny day.
Not only does direct sunshine help to conjure images of days at the beach, picnics at the park, or other pleasant outdoor activities, but it creates necessary physiological responses. These responses help regulate the release of melatonin, which determines sleep patterns, and serotonin, which influences mood and emotion. In fact, several health disorders can arise in people who are deprived of sunlight, from insomnia for night shift workers, to depression for those who are indoors most of the winter.
From a purely economic standpoint, employers and retailers alike understand the value of sunlight for its effects on worker morale and efficiency, and for its benefits in attractive product display. Those who spend hours under the gaze of fluorescent bulbs can tell you in no uncertain terms that when it comes to sunshine, there is nothing like the real thing.
However, in large offices and retail locations with large amounts of windowless interior space, sun can be hard to come by. Byard Wood, professor of mechanical and aerospace engineering at Utah State University, is working to bring the sun inside.
By utilizing fiber optic cables, similar to cables that power high-speed Internet connections, Wood is funneling sunlight through buildings in the same way that information is conveyed from computer to computer.
“Use of natural daylight has always been an important aspect inside buildings,” Wood says. “Natural light has the full spectrum, so it’s much softer than fluorescent or incandescent light.”
It’s easy to light rooms on the perimeter of buildings–just install windows. But until recently, there hasn’t been a way to channel natural light into buildings’ interior spaces. As part of a nation-wide partnership, Wood is developing a system that can capture natural light and funnel it just about anywhere.
Wood’s sunlight-capture begins atop a building where a parabolic, satellite-like device is placed to collect sunlight. The light is then transmitted into the building through fiber optic cables.
The special lighting systems have traditional fluorescent or incandescent bulbs for nighttime hours or cloudy days, but they also include an acrylic rod bulb for sunlight. Dimmers can be installed so the light intensity in a room doesn’t change, even when clouds pass overhead.
This is good news for companies hoping to maximize work from employees because “workers will naturally gravitate to the room with natural sunlight; it is just more pleasant,” Wood says. Natural light is also better for showcasing, so it’s attractive to museums and retailers that want to display their wares in the “best light,” so to speak.
“This is a concept that allows you some flexibility with the building design,” Wood says. “You can bring the light right where you want it.”
In fact, the world’s largest retailer has shown serious interest in using this technology. Wal-Mart is one of several large companies, including Staples and Aveda, that hope to use natural light to save on operational costs and make their products more attractive.
“We started with the idea of trying to save energy in commercial buildings–lighting is the dominant energy use for these facilities,” Wood says. “Companies like Wal-Mart are also very interested in this technology because it displays their products better during the day.”
These companies may be test sites for trial runs, too. In order to make this technology cost-feasible, it needs to be mass produced. But that can not happen until companies buy into the idea. Still, preliminary estimates are that companies in sunny places, such as Hawaii or Arizona, could save $1,500 per year in lighting costs per unit installed.
Wood is part of a nation-wide partnership trying to take this technology into the mainstream. Operating on a $3.7 million, five-year government grant, more than a dozen entities across the country have collaborated on this research, including Oak Ridge National Lab, University of Nevada—Reno, Ohio University, University of Wisconsin—Madison, Science Applications International Corporation, Rensselaer Polytechnic Institute, and the Tennessee Valley Authority. Sunlight Direct, a Tennessee startup company, licensed this technology for its business.
Wood’s engineering expertise was tapped to integrate the contributions of researchers from all these disparate entities. “My role is the system integration,” Wood says. “All the pieces of the system have to work together.”
Wood is also applying this research to energy development. As co-chair of USU’s executive committee on biofuels, Wood is studying how to use fiber optic-directed sunlight to grow algae on a large scale with the intent to produce biodiesel.
“At USU, we’re focusing on the concept of growing algae to produce fuel,” Wood says. This is the next step in the evolution of fiber optics. He says that the idea actually came from his earlier lighting project. Wood’s work on transporting sunlight indoors has a full spectrum of possibilities, which he is exploring through his ongoing research at USU.