How to Build a Solar Furnace

Over the years alternative energy sources have become very popular, and both persons and organizations are constantly researching ways in which they can save on fuel, one such alternative is solar energy which is generated from the sun. A Solar furnace is simply an installment that is used to harness energy from the sun. Whether you are making a solar furnace as a school project or for household use all you need are the right tools, time, and determination to make it work. The instructions are provided below

Tools required

  • Glass cutter (oil fed)
  • Screwdriver/Hammer

Materials required

  • Mirror glass
  • Plywood
  • Screws


  1. Take the mirror glass and feed it into the oil-fed glass cutter, making each about ¾ inch long. Make four of the pieces larger and find a location that receives a high degree of sunlight.
  2. Take the ½-inch thick plywood and pre-drill the holes then screw in the glass pieces onto the plywood to secure them on.
  3. Use the square pieces of mirrors and tilt the mirrors toward the middle of the plywood. Secure the spacing between the mirrors by using toothpicks with hot glue.
  4. Take the RTV silicone caulk and make a hinge at the mirror corner. Use a toothpick for the spacer again. Make the silicone harden and then fasten the mirrors with screws.
  5. All the mirrors excluding the one near the center should be covered. Take the solar furnace into the sun and use the one uncovered mirror as the reference to focus all of the other mirrors. This should store heat and then place the solar furnace in the direction of the area you wish to heat.

Tips and Warning

  • An alternative to oil-fed glass is using a diamond cutter. However, this is more time-consuming and a lot less accurate than using the oil-fed one.
  • There are generally two types of solar furnaces, monocrystalline, polycrystalline, and thin film. Monocrystalline has solar cells stacked in rows that are more round shapes, while polycrystalline is less expensive and has a more diverse arrangement and more square shapes. Thin film solar furnaces apply silicone material onto glass or stainless steel, these are things, that use less material and absorb light much easier.
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