What Type of Solar Reflector Will Make
a Solar Oven Get the Hottest?

Dominick C.
5th Grade, Suntree Elementary, Melbourne Florida
Teacher: Lynn Callahan & Jana Gabrielski

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Hypothesis:
The reflector that is able to focus the sun’s rays the best will make the solar oven the hottest. I believe the cone reflector will work the best.
(Professor Sunny's note: Dominick tested reflectors that were flat, parabolic and cone shaped.)

Conclusion:
The data showed that the flat reflectors made the solar oven get the hottest on both tests (got up to 295°F). This proved that my hypothesis was incorrect. This really confused me because all my research said that curved (parabolic) reflectors work better than flat ones. Also curved reflectors are used by scientists for giant solar furnaces that can get hotter than 1000°F, and I figured a cone would focus the sun’s light better than something with a little curve. So it should have done the best. I read back over some of the papers I got at FSEC and the Internet and found what I think is the problem. I am sure that parabolic reflectors work better than flat ones, but only if they are at an exact distance and position to focus all the sun’s light they are absorbing into the solar oven (otherwise they reflect the sunlight away from the solar oven), and I was not about to do that because of wind and it was hard to see exactly where the sun was being focused. The flat reflector worked better because it was easy for me to see where the sunlight was being reflected to.

In addition, the cone reflector focused the sunlight the best. I even tried it on my hand, and within a few seconds my hand started to BURN! But it didn’t work well because when I rolled it into a cone shape, I reduced the amount of area the reflector was using to reflect sunlight.

If I had to use a solar oven and reflector, I would choose a flat reflector because I could position it better. Although the parabolic reflector has more potential, it is much harder to make, use and position correctly.
(Professor Sunny's note: This is a second year study. Dominick used his discoveries of last year to design this year's project.)
View close-up of one of Dominick's reflectors