<P> Finally, aesthetics can be considered a factor in that some people find that the three - bladed rotor is more pleasing to look at than a one - or two - bladed rotor . </P> <P> In general, ideal materials should meet the following criteria: </P> <Ul> <Li> wide availability and easy processing to reduce cost and maintenance </Li> <Li> low weight or density to reduce gravitational forces </Li> <Li> high strength to withstand strong loading of wind and gravitational force of the blade itself </Li> <Li> high fatigue resistance to withstand cyclic loading </Li> <Li> high stiffness to ensure stability of the optimal shape and orientation of the blade and clearance with the tower </Li> <Li> high fracture toughness </Li> <Li> the ability to withstand environmental impacts such as lightning strikes, humidity, and temperature </Li> </Ul> <Li> wide availability and easy processing to reduce cost and maintenance </Li>

Why are wind turbines shaped the way they are