How to Build a Homemade Wind Turbine from Scrap Materials

Building a homemade wind turbine from scrap materials can be a fun and rewarding project. With some basic materials and a bit of ingenuity, I was able to build a small wind turbine that can generate electricity. Here is a step-by-step guide on how I built my homemade wind turbine on a budget.

Gather the Necessary Materials

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

• Blades: I used 3 old wooden pallet boards for the blades. Plywood, plastic or sheet metal can also work.
• Motor: I scavenged an old electric motor from a broken fan. Look for DC motors in old appliances.
• Tail: A large piece of scrap metal sheet to keep the turbine facing the wind.
• Body: The body was made from PVC pipe, but metal pipes can also work.
• Bearings: I used skateboard bearings inserted into the PVC pipe to allow the blades to spin freely.
• Alternator: I attached a small alternator to the motor to generate electricity. A car alternator works best.
• Charge controller: To regulate the power output and charge batteries. I used an inexpensive PWM controller.
• Batteries: Deep cycle lead-acid batteries to store the generated electricity.
• Metal scraps: For constructing the turbine mount and body.

I was able to source all of these components either from my own scrap piles or from junkyards for free or very low cost. The key is using what you already have on hand as much as possible.

Design and Size the Blades

The size and shape of the blades will affect how much power your wind turbine can generate. There are some key factors to consider in the blade design:

• Length: Longer blades can harvest more wind energy. My blades were 1.5 m (5 ft) but 2-3 m (6-10 ft) is ideal.
• Airfoil shape: The curved airfoil shape helps maximize lift. I cut my pallet wood into a rough airfoil shape.
• Pitch angle: Angling the blades (10-30 degrees) allows them to catch more wind.
• Number of blades: Most DIY turbines use 3 blades, but 2-5 can also work.

Use online wind turbine calculators to help determine the ideal blade size and shape for your materials and wind speeds. Cut your blades slightly longer than calculated to allow for adjustments.

Build the Turbine Frame and Mount

The turbine frame holds all of the components together in alignment. I built mine from 1.5 inch PVC pipe along with some metal scraps for support.

• Cut the PVC pipe to the desired lengths and join together with elbows and T joints. Leave one end open.
• Attach the bearing housings along the length to hold the motor.
• Make a simple metal mount to elevate and orient the turbine into the wind.
• Add guy wires from the mount to the ground to add stability.

Make sure the frame is sturdy enough to handle strong winds and the rotational forces of the blades. Use metal joints and supports where possible for strength.

Assemble the Core Components

Once the frame is ready, it's time to assemble the main components:

• Insert the motor into the bearing housings and attach with set screws or epoxy.
• Align the tail fin with the frame using a T joint and set screws. This keeps it oriented.
• Bolt the alternator securely onto the motor shaft. Make sure they rotate smoothly.
• Attach the charge controller near the back, along with a 12V battery.

At this point, the turbine should be able to spin freely on the bearings when moved by hand. Do some initial tests before attaching the blades.

Cut and Attach the Blades

The final step is cutting the blades to size and attaching them to the motor:

• Mark and cut the blades to the calculated length and airfoil shape.
• Using a protractor, set the blade pitch angle by angling the cuts at the blade roots.
• Attach the blades directly to the motor shaft using screws or hose clamps.
• Align them 120 degrees apart around the shaft for proper balance.

Start with a 30 degree pitch angle and make adjustments later if needed. Safety tip: Wear gloves when handling the blades, the edges can be very sharp.

Test, Troubleshoot and Optimize

With assembly complete, it's time to test out your new wind turbine!

• Carefully lift it up to the mounting frame and connect all the wiring.
• In light breezes, give it a spin to start generating power.
• If the rotation seems slow or uneven, adjust the blade pitch angles.
• Over several windy days, monitor the power output and adjust the blades or angle as needed.

Don’t get discouraged if your first attempt doesn’t work perfectly. Small adjustments to the blades and assembly can make a big difference. With some trial and error, you’ll get the hang of building turbines that can produce usable energy from scrap.

Building a homemade wind turbine was a great learning experience for me. And there's a sense of satisfaction being able to generate renewable electricity from recycled materials. With a resourceful mindset and some scrap materials, anyone can build their own wind turbine for an eco-friendly energy solution.