From doing research into solar applications I have come to the personal conclusion that solar energy is misapplied in many instances. Our sun is an awesome source of energy, but all too often we use it to create electricity we store to make heat or light later. While this has some really useful applications, each conversion looses some of the original energy. If we focus some attention on directly using the solar energy we get more “bang for our buck.”
There is a really good book called Sunshine To Dollars that has some really cool projects that give you an immediate return on you investment of time and energy.
So after reading this book and others like it, I decided to make a DIY Solar Cooker. I resisted the urge to make a huge solar oven out of a new fiberglass tub my old tenants inexplicably left in my basement. What I decided to do was to build a small wooden solar box cooker. It would have been easier and faster to build one of the many cardboard cookers that places like Build it Solar shows, but I figured that since the technology was pretty well developed this was not an experiment, and I should probably invest the energy into making a more robust and permanent cooker that I could use rather than a throwaway model for a proof of concept.
I decided on building one modeled after a cooker I saw on youtube. The user supergokuel had a really cool 2 part video, so I basically just modified his idea.
I could not find any replacement glass sheets at the local hardware store, but I did find a sheet of Optix brand clear plastic that would fit very nicely on the box I was trying to make.
The bigger your cooker the more efficient it will be, and the larger the pots you can use, so my 1×2 sheet of plastic will work well. I also bought some screws, hinges, and a 4×8 sheet of exterior grade plywood. The black paint and caulking I already had.
Basically I just cut two side pieces in a rectangle, and then cut a 45° angle down one side. I made the rectangle wide enough so that the angled end would be as long as the shorter side of the plastic. (I know this is confusing, this video helps).
The ends and bottom of the oven are cut to match the side pieces and are screwed together to make a box. The top is simply the clear plastic sheet of Optic attached to the box by hinges.
I painted the box black to absorb heat, and when I get more reflective film I plan on mirroring the inside of the box to help generate more heat. Larger box type collectors can get hot enough to bake or roast meat – upwards of 220°
This is a pretty simple project using hand tools and a power saw, but will allow you to cook many types of foods without electricity. For us disaster conscious types, the ability to bake and cook foods outdoors on something other than a grill or campfire has some serious advantages. For those that choose to reduce the use of resources – whether for ecological or self-reliant reasons, this is also a very useful project.
This is a project that I would highly recommend you duplicate of modify for your own usage.