Making a small scale model of a wind turbine can be a fun project to do on the weekend, helping to teach others about renewable energy systems. Small scale models can include a DC motor and a LED light bulb which the wind turbine powers to show how the turbine actually works. Building a small scale model can also serve as practice for some of the building techniques for a large scale wind turbine that can help to reduce home energy costs.
Cut PVC pipe wind turbine blades by quartering the PVC pipe with a hacksaw. Use a belt sander to fashion the pipe quarters into blades that resemble aeroplane wings with a curved, convex taper in the front and a narrow edge in the back. The blade should also become more narrow along its length towards the tip.
Mount three blades onto a DC permanent magnet motor from a used electric treadmill. Some treadmill motors may have a gear attached to them or shaft that protrudes from the generator motor. Use a tap and dye set to drill a hole in the gear ring of the DC motor if it is big enough for screwing on the PVC blades. Otherwise you may need to weld a larger gear or metallic disk onto the generator shaft. Bolt the blades onto the motor and test the motor with a multimeter for whether it generates electricity as you turn it.
Solder or screw in 12-gauge AWG cable to the generator's DC output ports, connecting the black wire to the positive port, red to the negative port and green to the motor housing as a ground. Solder a blocking diode to the AWG cable, which will prevent electricity from the battery from turning the turbine when the wind is not spinning the blades. Connect wire from the blocking diode to a charge controller.
Install the eyelets from the charge controller's output terminals to a deep-cycle battery. Adjust the charge controller to the voltage of the batteries and maximum amperage of the wind turbine system. The charge controller serves to prevent the battery system from becoming overcharged.
Wire 8-gauge AWG cable to the battery terminals by soldering the wire to eyelets, which you then screw onto the terminals. Depending on the purpose for your wind turbine system, you may want to install a power inverter to the battery rather than the AWG cable if there is a specific appliance that you want to power through the battery. Make sure there is enough voltage and amperage from the battery to power your appliance. Otherwise, solder an electrical switch to the AWG cable and solder wires from an LED bulb to the electrical switch.