quality:correction
Technology

Generally, efficiency increases along with turbine blade lengths. The blades must be stiff, strong, durable, light and resistant to fatigue. Materials with these properties include composites such as polyester and epoxy, while glass fiber and carbon fiber have been used for the reinforcing. Construction may involve manual layup or injection molding. Retrofitting existing turbines with larger blades reduces the task and risks of redesign.

As of 2021, the longest blade was 115.5 m (379 ft), producing 15 MW.

Blades usually last around 20 years, the typical lifespan of a wind turbine.