Electric Generator

Convert Mechanical energy to electrical energy

* This project guide is a modified version of the Wooden Generator project by MiniScience.com. All pictures are copyright of MiniScience.com and are being published with permission. 

Grades 8 to 12

Introduction: (Initial Observation)

Making an electric generator is a good way of learning the principles of generators. It also is an exciting science project. 

As a display project, you just need to make a generator and demonstrate it's structure. As an experimental project, you need to come up with questions about the factors that may affect the rate of production of electricity.


* This project guide is a modified version of the Wooden Generator project by MiniScience.com. With this modification you have choice to purchase all material separately and construct your generator from the ground up.

Information Gathering:
Gather information about your project. If you are a basic or advanced member of ScienceProject.com, your project advisor may prepare the initial information that you need and enter them in this section. In any case it is necessary for you to read additional books, magazines or ask professionals who might know in order to learn more about the subject of your research. Keep track of where you got your information from.

Electric Generator

When a conductor such as a copper wire cross magnetic fields, an electric force is created in the wire. Almost all electric generators have a rotor and a stator. Rotor is the magnet that rotates inside stator. Stator is made of one or more coils of wire.

Question/ Purpose:
What do you want to find out? Write a statement that describes what you want to do. Use your observations and questions to write the statement.

The purpose of this project is to build a simple electric generator. If you want to build an electric generator as a display project, you will not need any question.

If you want to do this as an experimental project, following are some suggested questions:

  1. How does the speed of turning rotor affect the production of electricity?
  2. How does the diameter of wire coil affect the amount of electricity?
  3. How does the number of loops of wire in the coil affect the amount of electricity?
  4. How does the diameter of coil wire affect the electric current?
  5. How do the material used in the construction of an electric generator affect the production of electricity?
Identify Variables:
When you think you know what variables may be involved, think about ways to change one at a time. If you change more than one at a time, you will not know what variable is causing your observation. Sometimes variables are linked and work together to cause something. At first, try to choose variables that you think act independently of each other.

Dependent and Independent Variables

The factor that you are testing is your independent variable. For example the speed of turning and diameter of wire are samples of independent variables. The rate of production of electricity is the dependent variable.

Based on your gathered information, make an educated guess about the answer to your question or the result of your experiment. 

Depending on the question that you select, you may predict an answer. That is called your hypothesis.

Experiment Design:
Design an experiment to test each hypothesis. Make a step-by-step list of what you will do to answer each question. This list is called an experimental procedure. For an experiment to give answers you can trust, it must have a "control." A control is an additional experimental trial or run. It is a separate experiment, done exactly like the others. The only difference is that no experimental variables are changed. A control is a neutral "reference point" for comparison that allows you to see what changing a variable does by comparing it to not changing anything. Dependable controls are sometimes very hard to develop. They can be the hardest part of a project. Without a control you cannot be sure that changing the variable causes your observations. A series of experiments that includes a control is called a "controlled experiment."

Electric Generator

Wooden Generator


If you are buying a kit, all the wooden parts are included and they are already cut to the size. So you just need to connect them. If you don't have a kit, prepare the wooden parts as follows:

  1. Cut two square pieces from the balsa wood (3.5" x 3.5").
  2. Make a 3/8" hole in the center of each square.
  3. Cut four 1" x 3 7/16.
  4. Cut a 3/4" piece from the 1" wood dowel. Make a 3/8" hole in the center of it. Insert a 6" long 3/8" wood dowel in the hole, apply some glue. center it and wait for it to dry. 
  5. Make another hole with the diameter of your rod magnet in the center of the larger wood dowel piece for the magnet to go through.
Wood dowels after completing the step 4
Wood dowels after completing the step 5

Adult supervision and professional help is required for all cuttings and hole makings.


  1. Insert the magnet in the hole of the wood dowel. Center it and use some glue to secure it.
  2. Use one large square balsa wood and four smaller rectangular balsa woods to make a box.
  3. Insert your wood dowel into the hole in the center of the box. At this time the magnet is inside the box.
  4. Place the other large square to complete the box. Apply some glue to the edges and wait for the glue to dry. By now, you have a box and inside the box you have a magnet that can spin when you spin the wood dowel.
  5. Wrap 200 turns of copper wire around the box and use masking tape to secure it. 
  6. Remove the insulation from the ends of the wire and connect it to the screws of the bulb holder or base. 
  7. Insert the light bulb
  8. Spin the wood dowel fast to get the light.


Materials and Equipment:

Following are the material that you need in order to construct a wooden electric generator.

  1. Wood dowel 3/8" diameter
  2. Wood Dowel 1" diameter.
  3. Rod magnet 3" long
  4. Insulated copper wire 27 AWG, 200 feet
  5. 1.2 Volt Screw Base light Bulb
  6. Base for the light bulb
  7. Small sand paper
  8. Wood Glue
  9. 1/2 Square foot Balsa wood (1/8" diameter)

Where to buy?

You may purchase wood from some hardware stores or home improvement stores or hobby stores.

Magnet can be purchased from hardware stores.

Insulated copper wire can be purchased from hardware stores 

A kit including all material pictured above is available at MiniScience.com.

Results of Experiment (Observation):
Experiments are often done in series. A series of experiments can be done by changing one variable a different amount each time. A series of experiments is made up of separate experimental "runs." During each run you make a measurement of how much the variable affected the system under study. For each run, a different amount of change in the variable is used. This produces a different amount of response in the system. You measure this response, or record data, in a table for this purpose. This is considered "raw data" since it has not been processed or interpreted yet. When raw data gets processed mathematically, for example, it becomes results.
If you do any calculation for your project, write your calculations in this section.

Summery of Results:
Summarize what happened. This can be in the form of a table of processed numerical data, or graphs. It could also be a written statement of what occurred during experiments.

It is from calculations using recorded data that tables and graphs are made. Studying tables and graphs, we can see trends that tell us how different variables cause our observations. Based on these trends, we can draw conclusions about the system under study. These conclusions help us confirm or deny our original hypothesis. Often, mathematical equations can be made from graphs. These equations allow us to predict how a change will affect the system without the need to do additional experiments. Advanced levels of experimental science rely heavily on graphical and mathematical analysis of data. At this level, science becomes even more interesting and powerful.

Using the trends in your experimental data and your experimental observations, try to answer your original questions. Is your hypothesis correct? Now is the time to pull together what happened, and assess the experiments you did.
Related Questions & Answers:
What you have learned may allow you to answer other questions. Many questions are related. Several new questions may have occurred to you while doing experiments. You may now be able to understand or verify things that you discovered when gathering information for the project. Questions lead to more questions, which lead to additional hypothesis that need to be tested.

Possible Errors:
If you did not observe anything different than what happened with your control, the variable you changed may not affect the system you are investigating. If you did not observe a consistent, reproducible trend in your series of experimental runs there may be experimental errors affecting your results. The first thing to check is how you are making your measurements. Is the measurement method questionable or unreliable? Maybe you are reading a scale incorrectly, or maybe the measuring instrument is working erratically.

If you determine that experimental errors are influencing your results, carefully rethink the design of your experiments. Review each step of the procedure to find sources of potential errors. If possible, have a scientist review the procedure with you. Sometimes the designer of an experiment can miss the obvious.



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