Wind Energy Picture

Forging the Future with Wind Energy at U.T. El Paso

Forging the Future, UTEP's new working motto, is especially appropriate considering the school's mining heritage as The Texas College of Mines. However, the future is now tied to "mining" our renewable resources, like the wind. The difference, of course, is this resource is inexhaustible.

The wind energy program at
Utep started in 1989 with a grant
from the State of Texas, Advanced
Technology Program, to develop
wind turbine engineering codes
and to build and operate an
engineering test site for advanced
two-bladed teetered rotor wind
turbines. The site, shown a right,
was constructed by faculty, staff
and students at UTEP and has
been operational since April 1993.
The goal is to support the comercial developmentof this type of wind turbine system.

Teetered rotor wind turbines use two blades rather than the usual three, which reduces the weight and initial cost of the turbine. In addition, teetering of the blades by use of a hinge pin where the blades attach to the rotor shaft reduces the loads and fatigue in the rotor system, which also reduces cost and improves reliability. All of the advanced turbine designs in the Federal Wind Energy Advances Wind Turbine Program are proposing to use this type of rotor, and the UTEP test facility is uniquely equipped to support the testing of teetered rotor wind turbines in a variety of configurations.

The basic configuration
uses a 7.6 meter diameter
teetered rotor turbine on a
60-foot lattice tower with a
10kW induction generator
and a 9:1gear ratio. The
tower base has been
designed to raise and lower
the tower in a few minutes
using a hydraulic system,
similar to the designs used
in the oil field to erect oil drilling rig towers. In the down position (pictured) the turbine components are only a few feet from the instrument control room, which facilitates easy checking of the components at the tip of the tower and rapid configuration changes. The design has been chosen to study the effects of some of the basic parameters of wind turbine rotors. Teeter springs and dampers can be added to the teeter hinge in the hub. The uptilt angle of the rotor can be varied in one degree increments from level to 10 degrees. The rotor can run upwind or downwind of the tower, and so forth. The system also has yaw motor which allows the rotor to be operated at high yaw angles, that is turned edgewise to the wind, and with variable yaw rates. An electric clutch allows free yas operation.

The test bed has comprehensive instrumentation and control system with computer data colection a telemetry radio link (right) for storage and analysis.

Presently the system is being used to investigate various teetered hub configurations. When these tests are complete, a new variable speed rotor system will be installed using a continuously variable transmission (left), manufactured by Excelermatic, of Austin, Texas, and a power electronics package, supplied by OEM Development of Boston, Massachusetts. Most wind turbines presently operate at a constant rotor speed. However, there is an opportunigy for increased energy capture and reduced turbine loads if the rotor is allowed to operate at a variable rotor speed.

Results from the research at UTEP will be available through technical papers presented to the American Society of Mechanical Engineers, the American Wind Energy Association, and the National Renewable Energy Laboratory. Contact Andy Swift at or Emil Moroz at .