Sol Cooker (design and construction)
The Sol Cooker is the result of desire to build a solar box style oven from common recycled items. The name is a poor attempt at humor by the builder. Good food is good for the soul. Soul cooking… Sol cooking. The builder has a real daytime job not involving comedy.
During the summer of 2005, Terry Jantzi a Kitchener Ontario resident, designed and constructed this cooker in approximately 3 hours. The majority of the materials were sourced at the Habitat ReStore located in Waterloo Ontario. The oven sides, braces, mirrors, mirror base, rear cover of indoor/outdoor carpeting and window were all purchased for less than CDN$30. The foil pipe insulation and assorted hardware fasteners were the only purchased items.
The rounded design was a result of a desire to solve three requirements. First was a need to easily aim the oven at the sun for optimum efficiency. The second requirement was to allow room for simple gimbaled pot holder. The third design requirement was to allow a shape where some parabolic capture and focusing of heat was possible. The indoor/outdoor carpeting was chosen for appearance and its mildew and rot resistance.
The first stage of the construction was to attach the two sides to the three braces. Ordinary drywall screws were used. The shape of the sides was determined by the size of the window that was purchased. The designer used a simple compass made out of a rope and pencil to draw circles until the window bisected the lines with enough room in the oven to fit a small oven roaster.
The carpet was stapled to the wood frame and trimmed.
The foil insulation was cut and stapled into the oven cavity.
The mirrors were mounted onto thin hardboard with an inexpensive construction adhesive. The hinges for the mirror are mounted as shown to allow for flush folding when not in use.
The front leg is screwed to the oven sides to allow the leg to pivot. The oven is rotated to the proper angle and the leg is positioned to lock it in place at that position.
How does it work?
Temperatures of 275F (135C) are easily reached at midday in July at a latitude of 43 degrees north.
Temperatures of 195F (91C) have been observed in January at midday with ambient temperatures of 20F (-7C) and light winds.
The oven has been in use since August 2005 and has cooked a variety of items such as rice, chicken, stews, beans, roasts, macaroni and cheese and bread.