How to Build a Small Scale Wind Turbine from Scrap

Building a small scale wind turbine from scrap materials can be a fun and educational project. Here is a step-by-step guide on how I built my own small wind turbine using mostly recycled parts.

Gather the Necessary Materials

The first step is to gather the materials needed to build the wind turbine. Here are the main components I used:

Alternator: The alternator converts the rotational energy into electrical energy. I salvaged a car alternator from a junkyard. Make sure to get one with permanent magnets.
Blades: The blades capture the kinetic energy of the wind. I used 3 wooden blades cut from scrap plywood.
Hub: This connects the blades to the alternator shaft. I machined the hub from an old steel rotor.
Tail: The tail keeps the turbine facing into the wind. I used a sheet metal tail vane.
Frame: The frame provides support for the whole structure. I welded pipe scraps together.
Bolts, screws, nuts, washers: For assembling the components. All salvaged.
Electrical wire, battery, charge controller: For the output system. I scavenged old cables and a car battery. The charge controller regulates the power.

Design and Build the Rotor

The rotor consists of the blades and hub. I designed three 24 inch long wooden blades for my small turbine using basic aerodynamic principles. Here are some key steps:

Cut the blades from plywood at 60 degrees using a protractor. The angle creates lift.
Sand the leading edges into a rounded airfoil shape. This improves efficiency.
Taper and twist the blades for better performance.
Bore a hole in the hub to attach each blade at 120 degree angles. This creates a balanced rotor.

Assemble the Nacelle Parts

The nacelle houses all the mechanical and electrical components. Here is how I assembled them:

Mount the stator side of the alternator onto a wood baseplate. This will prevent vibrations.
Attach the 3-bladed rotor onto the alternator shaft using nuts. Make sure it spins freely.
Install the tail vane with bolts onto an arm attached to the baseplate. This acts as the turbine yaw control.
Connect the cabling from the alternator terminals to the charge controller.

Construct the Tower

The tower elevates the turbine to catch more wind. I built a 15 foot tall tower using steel pipe segments:

Weld 3 legs made of 1.5 inch diameter pipes. They need to be strong and anchored securely into the ground.
Join the legs triangularly for stability and attach horizontal braces.
Slide 1 foot long pipe collars over each leg. They will support the turbine frame.
Lift and place the turbine assembly on top of the tower. Bolt it to the collars.

Connect and Test

The final steps are to wire up and test the wind turbine:

Run electrical cables down the tower from the nacelle to connect it to the battery and charge controller on the ground.
Ensure all connections are tight and insulated.
Initially, it is best to test the turbine without the blades connected. Spin the rotor by hand and check the voltage output.
If the alternator produces electricity, then connect the blades and do a spin test. The turbine should rotate smoothly.
Finally, run the complete wind turbine in actual wind and verify that the battery gets charged. Monitor the voltage and amperage.

With some scrap materials and basic skills, it is possible to construct a functional homemade wind turbine for renewable energy. Make sure to take proper safety precautions when building and operating your turbine. Let me know if you have any other questions!