How to Make an Electric Generator

Electric generators are "energy converters" that turn heat energy or kinetic energy (energy of motion) into electrical energy. The basic theory behind an electric generator is that variation of a magnetic field through a loop of wire produces an electric current through the wire. You can make a simple electric generator using some commonly available parts.

Difficulty:

Moderately Challenging

Instructions

Things You'll Need

• Energy source
• Wire
• Magnets

1. Determine the source of energy that you want to convert to electricity. You can use, for example, a stationary bicycle, a water wheel or virtually anything else with a rotating axle.

2. Coil a length of wire to form a reasonable-sized loop with the two wire ends accessible. The larger the number of turns in the loop, the more electricity you can generate.

3. Connect the wire loop to your energy source. You need to be able to rotate the loop end-over-end, without twisting the two connecting wires about each other. You can do this by connecting one wire to the rotating axle and the other wire to a conducting "brush" that maintains contact with a second conductor.

4. Ensure that you sufficiently support the loop and that it's out of the way of any moving parts of the energy source (such as your legs and the pedals if you plan to use a bicycle). This step may require reinforcing the loop with plastic or another light, but sturdy, material.

5. Arrange the magnets around the loop so that the loop can rotate freely between them. Also, make sure that you arrange the magnets to maximize the field strength. For example, you can do this by making the south end of one magnet face the north end of another.

6. Attach the two conductors on the energy source to a battery, device or circuit, as necessary. Like Step 3, this step may require some electrical and mechanical ingenuity.

7. Activate your energy source. This may be as simple as getting on the bike and pushing the pedals.

Tips & Warnings

• The magnitude of the electric voltage that you produce from your electric generator depends on such factors as the magnetic field strength, the size and number of turns in the loop, the speed of loop rotation and the quality of the electrical connections.

• This type of electrical generator produces alternating current (AC) electricity at a frequency that's determined by the rate of rotation of the loop.

• Make sure that the connections in Steps 3 and 6 do not form a short circuit. That is, there should be no electrical connection between the two wire ends, other than the loop. This is the most challenging part of the design.

• You can generate virtually any voltage you want, depending on how you build the electric generator. So, you need to be extremely careful as electricity can be lethal.

• Don't connect your generator to any battery or device until you're sure of both the level of voltage that you will produce and whether you need to design any circuitry as an interface.