How to Build Your Own Small-Scale Wind Turbine Generator

Introduction

Building your own small-scale wind turbine generator can be a fun and rewarding project. Generating your own electricity from wind power allows you to reduce your environmental impact and electricity bills. With some basic materials and tools, you can design and build a simple wind turbine that will provide enough power for small household needs. In this guide, I will walk you through the entire process step-by-step.

Components Needed

To build a small wind turbine, you will need the following components:

• Blades - The blades capture the kinetic energy of the wind and convert it into rotational energy. Plywood, plastic or composite blades can be used. 3 or more blades provide stability.

• Hub - The hub holds the blades in place and connects them to the rotor. This can be made from metal or wood.

• Rotor - The spinning part that converts wind energy into rotational energy. It consists of the blades and hub.

• Generator - Converts the rotational energy into electrical energy. A permanent magnet alternator or AC generator works well.

• Tower - Supports and elevates the turbine to capture stronger winds. Steel, wood or PVC can be used.

• Batteries - Store the electricity generated. Deep cycle lead acid batteries are commonly used.

• Inverter - Converts DC electricity from the batteries into AC electricity for household use.

• Controller - Regulates the electrical load and charging of batteries. Prevents overcharging.

• Wiring - Electrical wires to connect all the components.

• Hardware - Nuts, bolts, bearings and other parts to assemble the turbine.

Design Considerations

When designing your wind turbine, here are some factors to consider:

• Blade size - Longer blades can capture more wind energy. But the tradeoff is heavier weight and greater torque on the generator.

• Number of blades - More blades provide greater rotational torque. Three blades is the most common design.

• Blade pitch - The angle of the blades relative to the wind direction impacts efficiency. Variable pitch allows adjusting the angle.

• Rated power - Match your generator size to the turbine power output for maximum efficiency.

• Cut-in speed - The minimum wind speed at which the turbine starts generating power.

• Tower height - Higher towers access faster wind speeds and can greatly increase power production.

• Overspeed control - Prevents excess rotational speed that could damage components.

Construction Process

Follow these steps to build your wind turbine:

1. Design and Create the Rotor

• Decide on the size, number and shape of blades based on your needs and materials available. Larger surface area will capture more wind.
• Choose a design shape that is aerodynamic, such as a curved aerofoil cross section.
• Cut the blades out of wood, plastic or composite sheeting using a template.
• Assemble and attach the blades to the rotor hub using bolts, glue or ties.

2. Build the Tower

• Choose a height and location with the strongest and steadiest winds. At least 20 ft tall is recommended.
• Use tubular steel, wood, PVC or other materials to construct the tower in sections for easy transport and assembly.
• Include guy wires attached to ground anchors to stabilize the tower against strong winds.

3. Attach the Rotor

• Obtain a generator and assemble it onto the tower platform. Ensure it matches the power rating of your rotor.
• Mount the hub assembly onto the generator shaft using a coupling.
• Allow yaw control so the rotor can turn to face changing wind directions.

4. Add Electrical Components

• Connect the generator to a charge controller using large gauge electrical wire.
• Wire deep cycle batteries in sequence to store generated electricity.
• Install a power inverter to convert DC current into AC for household appliances and lighting.
• Add circuit breakers, surge protectors and meters to protect the system.

5. Erect and Test the Turbine

• Lift each tower section using pulleys and securely bolt them together.
• Guy and anchor the tower, then lift and attach the rotor and generator.
• Do initial testing at low wind speeds and ensure safe operation.
• When ready, your renewable energy wind turbine is complete!

Conclusion

Building a small wind turbine is an enjoyable and empowering project that pays off in free renewable energy. With some simple tools, materials and components, you can design and construct a fully functional turbine optimized to your needs and wind resource. Maintaining safety is paramount when working on this high structure. But once successfully built and installed, your turbine will provide clean electricity for years to come.