Sandia’s Segmented Ultralight Morphing Rotor (SUMR) will make possible a new low-cost offshore 50-MW wind turbine with a rotor blade more than 650 feet (200 meters) long, two and a half times longer than any existing wind blade (imagine it stretching across two football fields). One of these turbines could meet the electricity needs of 20,000 homes.
At lower wind speeds, the blades are spread out (like the horizontal axis wind turbines that you're familiar with) in order to maximize energy production. At dangerous wind speeds, like tropical storms or hurricanes, the blades are made to align with the wind direction, reducing the risk of damage. It may be possible that they could continue to spin like an egg beater set on its side.
The design was inspired by palm trees, which are able to survive severe storms by bending their trunks and folding their branches to align with the wind.