How to Build a DIY Wind Turbine from Scrap Materials

Introduction

Building your own wind turbine from scrap materials can be a fun and rewarding project. Wind turbines harness the power of the wind to generate electricity. Constructing a wind turbine at home allows you to produce your own renewable energy and reduce your carbon footprint.

In this comprehensive guide, I will walk you through all the steps I took to build my own small wind turbine from recycled parts and repurposed materials.

Things to Consider Before Starting

Before beginning your DIY wind turbine project, here are some important factors to consider:

Wind Resource Assessment

• Conduct a wind resource assessment for your location. Measure wind speeds using an anemometer at the planned turbine height.
• For a small turbine, annual average wind speeds of at least 11 mph (5 m/s) are recommended.
• Locations with high, steady winds like hilltops and open fields are best.

Turbine Size

• The size of your turbine will depend on your energy needs and available materials. Smaller turbines can power lights, appliances and charge batteries.
• Larger turbines have higher energy output but also require stronger materials and foundations.

Laws and Permits

• Check your local zoning laws and permitting requirements for wind turbines. Permits may be required for towers over a certain height.

Safety

• Proper engineering is crucial to prevent structural failure. Carefully follow plans and material specifications.
• Consider safety measures like an automatic braking system, warning signs, guide wires, and fencing.

Materials Needed

The scrap materials I used to build my small 500W turbine were:

• Wood for the tower and blades
• Old bicycle parts like wheels, tubes and chains
• A car alternator to generate electricity
• Scrap metal for the turbine mount, arms, bolts and nuts
• Electrical wires and components like a bridge rectifier
• Cement for the turbine base

I also used basic tools:

• Power drills, saws
• Wrenches, screws, nails
• Volt meter, welding equipment

Turbine Tower Design and Construction

The tower holds your wind turbine high up where wind speeds are faster. My DIY tower design was made from:

Materials

• 3" diameter metal pipes for the main structure
• Metal plates for the base and stabilizing arms
• Wood boards for the platform

Assembly

• I welded the pipes together into a triangular shape for stability.
• The tower stands 20 feet tall to elevate the turbine above roof height.
• I bolted metal arms halfway down the tower to reinforce it.
• The wood platform at the top supports the turbine mount.

Foundation

• A concrete foundation keeps the tower rigid and upright.
• I dug a hole 3 feet deep and filled it with quick-setting concrete.
• Insert the metal base plate while the concrete is still wet.

Turbine Mount Design

The mount attaches the turbine to the tower and allows it to yaw into the wind. My mount consists of:

• A vertical steel pipe fitted into the tower platform to act as the main axle.
• Two sturdy metal arms bolted to the axle. The turbine will be fixed to these arms.
• A diagonal stabilizing bar welded between the two arms to reduce vibration.
• Two bike wheel rims welded at the ends of the arms allow the turbine to freely spin around the vertical axle.

Turbine Blade Design and Construction

The blades capture the wind energy and convert it into rotational motion. My DIY turbine blades:

Materials

• Plywood sheets for the blade frames.
• Corrugated plastic from old signs to cover the plywood. This creates a curved aerofoil shape.

Assembly

• I made three twisted blade frames out of plywood, each 5 feet long.
• The plastic sheeting was cut, heated and shaped over the plywood to complete the blades.

Pitch Angle

• The blades were set at a 30 degree tilt to maximize rotation speed.
• Hinges attach the blades onto the arms so the pitch can be adjusted.

Alternator and Electrical Components

To generate electricity, my turbine uses:

• A car alternator fixed to the mount arms and spun by the rotating blades.
• A bridge rectifier converts the alternator's AC output into DC current.
• Wires carry the electricity down the tower into my workshop.
• The power is stored in lead-acid batteries before being inverted back to AC.

Safety Features

I incorporated a few key safety features:

• Metal guy-wires anchored into the ground to prevent tower toppling.
• Hinge joints allow the blades to fold back in high winds to avoid damage.
• Reflective tape on the blades to warn aircraft.
• A chain brake to manually stop the turbine.
• Warning signs on the tower, electrical boxes and fence.

Conclusion

Building a DIY wind turbine from scrap materials was a challenging but rewarding project. I successfully generated clean renewable energy through the power of wind. This guide covered the essential steps like assessing your location, designing the turbine and tower, sourcing materials, construction and safety. With some determination and elbow grease, you can build your own scrap-based wind turbine too!