Wind turbines taller than Empire State Building?
From ZME Science
In wind energy, bigger is almost always better. With this in mind, six leading universities and institutions have banded together to design that world’s largest wind turbine yet. Standing at 500 meters (1,640 feet), the SUMR project will be about 57 meters taller than the iconic Empire State Building. The concept features two 200-meter (650-foot) turbine blades which are twice the size of an American football field.
Over the last two decades or so, wind turbines have become larger and larger. In the 1980s, the largest wind turbines had a rotor diameter of only a couple tens of meters. Today, land-based supply is dominated by turbines in the 1.5 and 2 MW range — enough to power 500 American homes — and typical wind farm towers stand around 70 meters tall. This dramatic evolution in size is no accident because power output depends on the rotor blades’ size and the wind turbine tower’s height.
The higher up the turbine is, the better the winds are and the more kinetic energy can be harvested. A taller structure can thus capture more energy. It also enables lengthier blades and a larger swept area — the circular area drawn by a blade’s rotation. Interestingly, a turbine’s power output doesn’t linearly increase with the blade’s size. Because the swept area is what matters, if a system’s blade length doubles, the power output can actually quadruple.