a trillium wind turbine has an electricity - generating nacelle and swept - back , complexly - curved blades . each blade has a main blade , a trailing edge blade , and a diversion blade . wind is directed down the length of the blade and exits the tip . the main blade resembles a portion of a cylinder in form , the cylinder being twisted to change the angle of attack , thereby adding more lift throughout the length of the blade . the trailing edge and diversion blades are pitched relative to the wind and produce lift . additionally , wind hitting the diversion blade is diverted behind the blade . because the surface area and volume of the blade are larger near the nacelle and smaller at the tip , the air that travels along the blade increases in velocity as it travels producing more thrust / lift . the turbine also automatically faces into the wind without the need for sensors or positioning motors .