How to Use a Car Alternator to Make Alternative Energy

car alternator
  • 3-6 hours
  • Advanced
  • 0-1,000
What You'll Need
Old alternator
What You'll Need
Old alternator

There are many different ways to use something to create alternative energy. An old car alternator can provide one of those ways! In a vehicle, an alternator is used to charge the battery. As such, once it begins to produce electricity, it can keep itself moving without any additional work. Here is a quick project that will give you the ability to use an old, working alternator as an alternative source for energy.

Step 1 - Choose the Right Alternator

The type you want to use for this project should be an older design, such as you might find in a scrap yard. A large percentage of the alternators come with internal regulators to control the charging rate, so try and pick one of these up to keep hook up and installation to a minimum.

Step 2 - Connect the Alternator

Connect the device to a 12-volt battery to provide stability in the system. Connect the largest terminal of the alternator to the positive terminal of the battery; the negative terminal of the battery connects to the frame (housing) of the alternator. Two or three smaller terminals will remain depending on the design.

With the two-terminal design it usually means that a regulator is built in, and you need to attach one terminal to battery positive and the other small terminal, through some type of switch, to a positive voltage source. This turn-on circuit energizes the regulator and will control the alternator output voltage to a maximum of approximately 14 to 14.7 volts.

With a three-terminal design it usually means you have to mount an external regulator and run the corresponding wiring from the alternator to the regulator and the battery positive. Turn on positive voltage, and then go to the regulator instead of the alternator. If you want to use the alternator as a backup source of power when your regular system fails, consider using a small gas powered engine like one from a lawn mower.

Step 3 - Bolt the Alternator

Bolt the alternator to the deck, and attach a pulley on the output shaft of the gas motor to drive the alternator through a belt.

Step 4 - Power it With Green Sources

If you are considering using this alternator to generate energy, try attaching it to a pole and mounting a blade type fan or propeller to the shaft. Place this assembly in a windy location for Mother Nature to turn it. Or, if you live beside a running stream or body of water, mount a paddle wheel on the alternator and allow the water to do the work. Remember that the alternator itself cannot be immersed in the water and should be protected from large amounts of spray.