solar concentrators

The Hawks have started working on their group Expression project for Mirrors: making solar marshmallow roasters. Inspired by their work from before spring break, each Hawk is taking a different approach to the solar concentrator challenge. Mackenzie reports that she and the Hawks are determined not to make the Expression project a competition between each student, but rather an opportunity to share ideas openly, credit each other's work, and build on each other's successes and failures. Already they have started forming partnerships and alliances between themselves as their ideas and strategies begin to line up!Aurora and Natasha were inspired by the Archimedes Death Ray episode of Mythbusters and spun Plaster of Paris to make a parabolic shape for their solar concentrator.They learned that a parabola is a slice of a cone that goes on into infinity, which makes it good for gathering light! After learning that very little sticks to Plaster of Paris, they settled on covering their parabola with reflective tape and created a clear focal point.Now they have to figure out if their parabola is big enough to generate enough heat to roast a marshmallow.Bruno also made a parabolic Plaster of Paris mold, but covered his with mirror tiles instead of reflective tape.He was inspired by the disco ball hanging above the cork floor and resolved to make an inside-out disco ball for his solar concentrator.Mackenzie writes, "If you look into Bruno’s parabola and align your eye with the focal point, you will see a dozen of your own eyes looking back. This is how you know that all the mirrors are correctly placed to reflect light to the focal point."Quinn experimented with several different conical reflective surfaces as well as the ideas of several of the other Hawks.He found an old satellite dish at home and covered it in reflective tape, then added mirror tiles to give it a boost in reflecting light and creating heat.Ben made several small iterations where he experimented with creating stronger and stronger focal points. He tried a light fixture lined with foil and a piece of U-shaped bucket lined with reflective tape. But none of the of the focal points were strong enough.Ultimately, he decided on a hanging piece of reflective material in a frame to create a large hanging parabola.Lola and Lucy would like to bake a pie in their solar concentrator. They found a Styrofoam container in storage and painted the outside black so that it will absorb more heat.They lined the box with foil and put a plexiglass cover on the open end. When they tested it the first time, it already reached 250 degrees!On Friday they took their first iterations outside to test them and found the hot spots for each. They will continue with next iterations this week!