How to Build a Magnetic Generator

A magnetic generator.
A magnetic generator shows the principle that magnetism plus movement produces electricity. Bosca78 / Getty Images

A magnetic generator demonstrates the principle that magnetism plus movement produces electricity [source: Weidner, Brown]. This straightforward principle is behind the current interest in using a magnetic generator to produce electricity for the home. We'll start by building a small model, that will demonstrate the same principle as the generator you might consider building for your home.

Materials needed


  • Small sheet of cardboard
  • One nail, about 6 inches (15 centimeters) long
  • Insulation tape
  • 28 feet (8.5 meters) of thin insulated copper wire
  • Small bulb in a bulb holder

Here's what to do:

  1. Cut out two circles from the cardboard, about 1½ inches (3.8 centimeters) in diameter.
  2. Make a hole in the center of each circle.
  3. Push a clean nail through the hole in one of the circles. Push the cardboard circle up to the head of the nail.
  4. Cover about 1½ inches (3.8 centimeters) of the nail with a single layer of insulation tape.
  5. Push the second cardboard circle onto the nail, up to the end of the insulation tape. Fix the circle in place with more insulation tape.
  6. Wind the copper wire in between the two cardboard circles, over the insulation tape. Leave about 8 inches (20 centimeters) loose before you start winding the wire. You'll probably have to wind the wire around at least 1000 times. Leave about 12 inches (30.5 centimeters) free after the wire has been wound.
  7. Tape the spool of wire into position so it doesn't come undone.
  8. Strip the insulation off the ends of the wire and attach them to the bulb holder connection.
  9. Place the magnet ¼ inch (.6 centimeters) from the head of the nail and move it rapidly from side to side [source: Hare]. The bulb will light up!