Vertical-axis

The axis of rotation is vertical with respect to the ground and roughly perpendicular to the wind stream.  Vertical–axis wind machines have blades that go from top to bottom and the most common type (Darrieus wind turbine) looks like a giant two-bladed egg beaters. The type of vertical wind machine typically stands 100 feet tall and 50 feet wide. Vertical-axis wind machines make up only a very small percent of the wind machines used today.

There is a new generation of wind turbine currently being developed called the Wind Amplified Rotor Platform (WARP).  This is a different kind of wind system that is designed to be more efficient and use less land than wind machines in use today. The WARP does not use large blades; instead, it looks like a stack of wheel rims. Each module has a pair of small, high capacity turbines mounted to both of its concave wind amplifier module channel surfaces. The concave surfaces channel wind toward the turbines, amplifying wind speeds by 50 percent or more. Eneco, the company that designed WARP, plans to market the technology to power offshore oil platforms and wireless telephone communications. 

Kid’s Page Continued . . .

 

Horizontal-axis

The axis of rotation is horizontal with respect to the ground and roughly parallel to the wind stream.  Most wind machines being used today are the horizontal-axis type. Horizontal-axis wind machines have blades like airplane propellers. A typical horizontal wind machine stands as tall as a 20-story building and has three blades that span 200 feet across.  The tower is usually hollow and made of steel.  The blades, called rotors, are made of fiberglass and polyester.  The largest wind machines in the world have blades longer than a football field! Wind machines stand tall and wide to capture more wind.