Every time you turn on the stove to boil water, you are using energy you don’t have to. The sun can do it for you. A solar oven is little more than a black box with reflective surfaces that focus the sun’s rays. If you have intermediate carpentry skills and a little time. It’s easy to build one that will produce temperatures of more than 400 degrees Fahrenheit. Enough to boil water and even cook your dinner.
Making a Solar Oven By Brainergiser :
Tools and Materials
- Plywood, one sheet, 1/2-inch thick
- Circular saw
- Phillips screw bits, No.1 and No.2
- Tape measure
- 8 corner brackets, 1/2-inch
- 16 screws, 1/2-inch
- Carpenter’s glue
- 6 feet of 1-inch by 3-inch hardwood
- Screws, 1 1/4-inch
- 2 feet of 1-inch by 1-inch hardwood
- Two-part epoxy resin
- Cut the following for a rectangular box that slopes downwards from back to front from ½-inch plywood. Two pieces that measure 16 by 12 inches and 16 by 8 inches, respectively, for the back and front. A square of 17 inches for the bottom; two slanted shapes 17 inches long with back heights of 12 inches and a front heights of 8 inches for the sides.
- Affix two ½-inch corner brackets to inside of the front, back and bottom of each of the side pieces using ½-inch screws. Leave a ½-inch gap between the corner bracket and the edge of the board so that the front, back and bottom pieces can be joined there.
- Assemble the box with ½-inch screws, using glue to secure the joints.
- Use 1-by-3 hardwood to frame the top edge of the box, applying a bead of glue before screwing on the frame with 1-1/4-inch screws. This frame should have an outer perimeter of 20 inches. Add a 14-inch piece of 1-by-1 hardwood on the surface of this frame in the middle of the higher, back end of the box to support the reflector. Cut another piece of 1-by-1 about a foot long to make one leg and attach it to the back of the box so that it raises the back end a further 4 inches.
- Cover the entire box, inside and out, with two or three layers of epoxy resin. When it is dry, spray the epoxy with high temperature flat black stove enamel.
Instructions for Making the Cover and Reflectors
- Use tin snips to cut four pieces of sheet metal to dimensions of 17 by 23 inches. Make a small diagonal cut at each corner and use pliers to fold the edges over about ½-inch and crimp them. The final dimensions of each of these reflectors will be 16 by 22 inches after the edges have been folded over.
- Measure 1 inch from each bottom corner along the long edge of one reflector and make a mark, then measure 6 inches along the short edge from each bottom corner and make another mark. These marks define a triangular piece to be cut out from each of the bottom corners. Cut these out with tin snips. Repeat this for the other three reflectors.
- Cut one of the reflectors in half in the following way: mark the center of the top edge and cut in a line perpendicular to it. You will then have two identical pieces measuring 16 by 11 inches, each with a corner cut away. Use a riveter to join them with 14-inch hinges so that the reflector is identical to the original piece, that is, with the cutouts on the outside edges, only now it is hinged in the middle. Repeat with one more reflector.
- Rivet 5-inch hinges to the corner cutouts on these hinged pieces and join them to the front and back, unhinged, reflectors. You will now have a reflector that opens like a funnel to collect sunlight and collapses when you push the sides in towards the center.
- Rivet a 14-inch hinge to the bottom edge of one of the unhinged pieces and attach this hinge to the 1-by-1 hardwood on the back trim of the oven.
- Attach two standard mirror holders to the front trim piece and two the back so you can slide a 16-by-16 inch piece of glass over the top of the oven.
Instructions for Making a Cooking Basket
- Cut out another piece of sheet metal 12-by-26 inches (with folded edges).
- Make marks along the long edges that are 7 inches from the ends and bend the ends up 90 degrees relative to the center to make a hang-able tray with a 12-inch horizontal surface.
- Paint it black with high temperature enamel.
- Drill ½-inch holes about 1 inch from each end and attach this tray to the inside of the oven by putting lag screws through the holes and screwing them into the sides of the oven. It should be securely attached but be able to swing freely.
Be careful when you use this oven and don’t be deceived by its relatively harmless demeanor. The contents will be hot after it has been in the sun for a while, and you will need oven gloves to handle them. Prolong the life of your oven by keeping it indoors when not in use.