GE has attached an 18-metre wide dome to a 1.7MW turbine at its Tehachapi facility, California. The turbine is installed on GE's 91-metre space frame tower.
GE said its 'ecoROTR' dome deflects the wind towards the blade tips, boosting the amount of energy the turbine can harvest.
The design was revealed on GE's online magazine GEReports. GE's leader of sustainable energy projects, Mike Bowman, told the website: "It almost looks as if an UFO got stuck on the face."
Bowman added: "The design looked really strange, but it made a lot of sense. When wind hits the centre of the wind turbine where the blades are attached, it is wasted. That is because the blades are basically levers and the same wind generates more force further from the hub."
Following tests in on a model in a wind tunnel, GE's engineers saw the dome could add up to 3% of performance to a turbine.
The ecoROTR has been developed over two years after GE challenged its scientists to make a more efficient rotor without lengthening the blades. GE said the design could result in larger rotor sizes as the blades may be attached to the dome's edge.
To begin testing the design, GE engineers used a toothpick and glue to stick half of a small Styrofoam ball to the front of a model turbine.