Manufacturers are able to produce ever larger wind turbines. With larger rotor blades, a modern wind turbine can produce relatively more clean energy, decreasing CO2 emissions even more. Larger wind turbines also help lower the costs of renewable energy.
Why are larger wind turbines so efficient? If the rotor blades of a wind turbine double in length, the turbine catches four times as much wind (not two times). This is because the surface of the circle which the rotor blades make consists of the square of the length of these blades (multiplied by the constant value π).