Wind Turbine Blades

Wind Turbine Blades

Materials used in construction

  • Wind turbine blades are often made of composite materials like fibreglass reinforced plastic (FRP), due to their desirable balance of strength, rigidity and low weight.

  • Some blades incorporate carbon fibre for added strength and stiffness, although it’s more expensive and more conductive than fibreglass, it can be beneficial in blades over about 60 meters long.

  • The core materials of the blade are often made from lightweight polymers such as PVC, PET, or balsa wood for structural integrity while keeping the weight to a minimum.

Design & Structure

  • A blade’s length and shape (aerodynamic profile) can significantly impact a wind turbine’s overall efficiency. The blades are generally tapered and twisted to transform as much wind energy into rotational motion as possible.

  • The inner part of the blade, the root, is designed to be thick and strong to withstand wind forces, whereas the tip of the blade is thin and flexible to minimise noise and vibration.

  • Incorporate lightning protection systems within the blade. This usually consists of a metal receptor on the blade’s outer surface, metal down conductors along the blade, and grounding equipment to direct lightning discharges safely to the ground.

Manufacturing Process

  • The manufacturing of wind turbine blades generally involves a moulding process. The blade materials are layered into a mould in a precise sequence and orientation, and then bonded together using heat or room temperature curing methods.

  • Blade manufacture also sometimes involves post-curing. The newly moulded part is heated in an oven to ensure complete curing and to improve material properties.

  • A surface finish, such as a layer of protective paint, is applied to the blade to protect it from environmental damage, including ultraviolet light, moisture, and erosion.

Maintenance & Life Cycle

  • Regular inspections and maintenance are necessary for wind turbine blades, given their constant exposure to the elements. Inspections can detect issues like cracking, delamination, lightening damage, and erosion.

  • End-of-life disposal of wind turbine blades is an important but challenging aspect of their material lifecycle, due to their large size and composite material construction, which can be difficult to recycle.