Solar Powered Hot Dog CookerHeat Transfer Lab – University of Pennsylvania (2011)
For this lab, the objective was to create a device that would use solar radiation to accomplish a task.
I had seen solar hot dog cookers on the Internet before, but I had always wanted to make one for myself. As well, I wanted to explore another aspect of engineering design in tandem with the class requirements. While most of the solar hot dog cookers I had seen were made from sturdy constructions of plywood and lumber, I was determined to create one from inexpensive materials that could be easily assembled, taken apart, and flat packed, similar to the brilliantly economical design that Ikea uses for its flat-packed furniture. I also imagined that this sort of design exercise would be useful for products aimed at the developing world. I made the parabolic dish from 1/8” thick laser-cut MDF boards, poster paper, tin foil, and toothpicks. Altogether the cooker cost less than $5 in materials, could stack neatly to be hidden away, and could be reassembled in minutes without having to refer to any confusing Ikea-like directions. The cooker was designed to focus one fifth of a square meter of sunlight at the hot dog, and after considering all the potential losses, this came out to be about 10 watts of net heat flux.
The cooker was able to heat the hot dog to 150º F within 10 minutes time, which was surprisingly close to what the calculations predicted for how imperfect the tin-foil reflector was. As well, the hot dog tasted much better than usual, but that’s probably because I had worked so hard for it.