Tuesday, March 16, 2010

It's Solar Tube Time ~ Lessons in Light!

Due to the architectural design some of our rooms do not have external windows. In spite of that restriction, the lighting in this room does have some amount of natural solar lighting.
You will notice there are two sources of light in this ceiling shot. We have hanging fluorescent lights. These lights are different from traditional fluorescent which only provide down lighting. These new lights are designed to shine upwards and reflect off the ceiling tiles. (Notice the glowing on the ceiling). The square section of light in the center of the photo is the solar tube lighting.
This photo shows the solar tube lighting with all other lights turned off. This photo was taken on a cloudy, gray, raining, and fully overcast day. And yet a full glow of light is emitted. How is that? Reflection and refraction amplify the amount of light!
In the photo above one can learn an interesting detail about reflection. These silver tubes are solar tubes being assembled out in the commons area. When installed these stainless tubes are attached to a louvered panel on the roof and provide a continuous "tube" from the outer roof to the ceiling of the rooms where the lens are installed. It is through these tubes that sunlight is captured.
If you notice the two tubes that are not under one of the lobby lights you will see they appear to be normal stainless steel and there is little difference in the outside and the inside of the tube.
Take notice of the tube which is on the left in the first photo and sits under one of the lobby lights. You will notice there is a highly reflective surface that glows and bounces light down the length of the tube. I thought this shot provided an excellent demonstration of how reflected light intensifies in a tube.

The tubes are then connected to the room and a 2 X 2 foot lens is installed in the drop ceiling panels.
This is a close up of the square lens plate shown above in the first two photos in this post.
Each of the small cells in the in the glass of the panel contains a refracting lens that distributes and amplifies the sunlight much like the glass lens of a lighthouse amplifies and projects light.

The next few photos show the sequence of the process of the closing the louvered panels on the roof that feed the solar tube.
You are looking up into the tube in each of these lens "eyes".
Nearly fully closed you can actually see the louver in the convex of the lens.
The mechanics are controlled by a motor and the switch is in each classroom that has these solar tubes installed.
In this photo a lesson in the physics of light can be found and taught. Notice the refraction of the light as it passes through the lens. Sunlight contains all colors of the spectrum. You will recall from your science study that when light passes through a prism it is broken up into the colors of the spectrum.

By focusing my camera lens precisely on the surface of the lens one can see the distribution of the full color spectrum through the lens. (Remember ROYGBIV ?)

It is in this manner that we receive "full spectrum lighting" from sunlight.
Upon close examination one can see the Fresnel lens in the center as concentric rings. Thus, our building as a teaching tool as well as a learning center!

1 comment:

Solar Tubes said...

Wow! What a great opportunity to teach students about the science of light using a real life project!

We would love to write a blog post about this on our site.

Would you be OK with us doing that?

Here is our site, please contact us if you are OK with us creating a story about this.

ECO Solar Tube Skylights

Randy