Modern wind turbine rotors spin around 8-16 revolutions per minute (RPM). For this reason, a gearbox is used to step up the rotation speed roughly 100x from the rotor to the generator.
The residential and commercial reference distributed wind system LCOE are estimated at $240/MWh and $174/MWh, respectively. Single-variable sensitivity analysis for the representative systems is presented in the 2019 Cost of Wind Energy Review (Stehly, Beiter, and Duffy 2020).
Typical cost range for a single wind turbine blade spans from roughly $80,000 to $350,000, depending on blade length, composite materials, and engineering requirements.
High-speed winds, typically above 25-30 mph (40-48 km/h), can cause a turbine to reach its maximum power production capacity quickly. At this point, any further increase in wind speed won't lead to more energy generation due to aerodynamic limitations.
SANY Renewable Energy, a wind turbine manufacturer in China, has built the world's longest onshore wind turbine blade. The SY1310A is 430 feet (131 meters) long and rolled off the assembly line on January 21 at SANY's zero-carbon, smart industrial park in Bayannur, Inner Mongolia.
According to The United States Department of Energy, most modern land-based wind turbines have blades of over 170 feet (52 meters). This means that their total rotor diameter is longer than a football field.