The wind turbine manufacturing process involves multiple stages — from raw materials to final assembly — and integrates mechanical, electrical, and composite engineering. Here’s a detailed step-by-step breakdown of how a modern utility-scale wind turbine (like those used in wind farms) is manufactured:
1. Design & Engineering
Before manufacturing begins, engineers:
- Perform aerodynamic, structural, and electrical design using simulation software.
- Optimize for efficiency, durability, and site-specific wind conditions.
- Select materials based on weight, strength, and corrosion resistance.
2. Blade Manufacturing
Wind turbine blades are typically made of composite materials (fiberglass or carbon fiber reinforced with epoxy or polyester resin).
Steps:
- Mold Preparation:
- Large molds (often 50–100 m long) are cleaned and coated with a release agent.
- A gel coat may be applied for surface protection.
- Layup of Reinforcement Layers:
- Layers of fiberglass or carbon fiber fabric are laid into the mold.
- Pre-cut mats are positioned to form the internal structure.
- Spar & Core Insertion:
- A spar cap (main structural beam) and foam or balsa core are placed for stiffness.
- Resin Infusion or Prepreg Curing:
- In vacuum infusion, resin is drawn through the fibers using vacuum pressure.
- In prepreg methods, fibers are pre-impregnated with resin and cured in an oven.
- Curing:
- The blade is heated (in molds or autoclaves) to harden the resin.
- Bonding & Finishing:
- Two halves of the blade are bonded together with epoxy adhesive.
- The surface is sanded, painted, and inspected for defects.
3. Tower Manufacturing
The tower is usually rolled steel, occasionally concrete or hybrid.
Steps:
- Steel Plate Rolling:
- Flat steel plates are rolled into cylindrical or conical sections (tower segments).
- Welding:
- Longitudinal and circumferential welds are made and inspected (ultrasonic or X-ray).
- Surface Treatment:
- Shot blasting, priming, and painting protect against corrosion.
- Internal Fittings:
- Ladders, platforms, cable conduits, and electrical wiring are installed.
4. Nacelle Manufacturing
The nacelle houses key mechanical and electrical components at the top of the tower.
Main Components:
- Main shaft & bearings
- Gearbox (if not direct drive)
- Generator
- Yaw system (rotates nacelle toward wind)
- Cooling & braking systems
Process:
- Machining of Metal Components: Shafts, housings, and hubs are precision-machined.
- Assembly of Gearbox and Generator: Components are mounted on the nacelle frame.
- Electrical Integration: Sensors, converters, and control units are wired.
- Testing: Each nacelle undergoes dynamic balancing and functional tests.
5. Hub & Rotor Assembly
- The hub (often cast iron) connects blades to the main shaft.
- Pitch control systems are installed to adjust blade angles.
- Each blade is bolted to the hub, forming the complete rotor.
6. Transportation & Logistics
- Blades, tower sections, and nacelles are transported (often by truck or ship) to the installation site.
- Logistics planning ensures roads, bridges, and cranes can handle the size and weight.
7. On-Site Assembly & Commissioning
- Tower Erection: Sections are stacked and bolted with high-strength bolts.
- Nacelle Installation: Lifted onto the tower with a crane.
- Rotor Mounting: The rotor assembly is attached to the nacelle.
- Electrical Connection: Turbine is wired to the control system and grid.
- Testing & Commissioning: Systems are calibrated and tested under load.
8. Quality Control & Sustainability
- Non-destructive testing (ultrasound, X-ray, thermography) ensures integrity.
- Increasing focus on recyclable blades, low-carbon steel, and lifecycle assessment to reduce environmental impact.