Solar Lighting

Here is an article I found regarding solar lighting. It discusses a method using hybrid solar lighting and I think it would be a good idea to incorporate something similar to it or at least follow some of its principles. One drawback of this is that it could be expensive.

It's called Hybrid Solar Lighting. It's half solar and half electric. During the day, sunlight pours out of the light fixture; at night, a conventional light bulb takes over. So it's a hybrid.

How do you get sunlight to the fixture? With bundles of optical fiber--light pipes leading up to the roof. On the roof is a large dish that does not point at a satellite; it points at the sun. It concentrates the sun into the end of the fiber bundle.

The sunlight bounces twice. Once, off the big mirrored dish, then off of a smaller secondary mirror, which focuses everything down into the fiber optics. The mirror actually filters out the ultraviolet and the infrared rays. You don't have to worry about getting sunburned indoors.

What makes it practical are new plastic fibers and a sophisticated tracking system that points precisely at the sun, no matter the time of year.

There is even a psychological benefit, according to Kostas Papamichael, Associate Director of the California Lighting Technology Center in Davis. "We know that people like daylight," he says. "We know that daylight gives the best color rendering. It links us to the environment and satisfies biological needs that we have. Not necessarily at the level that you get it from a window -- and, next to it, by a skylight -- but some connection to the exterior for sure."

For our interview, we lit Kostas Papamichael entirely with sunlight from the roof, bright and clear. What's not so clear is the cost benefit. The California Lighting Technology Center is conducting an independent scientific study for the developer, Sunlight Direct. So far, it looks good, especially in a hybrid configuration. What looks like a fluorescent light bulb is actually a single, huge optical fiber. Install the fiber alongside a real fluorescent lamp and you have a 24-hour solution.