Wind Turbine Products

Towers

• A tower extends the generator above surrounding obstructions, such as trees, hills and buildings. The design of the tower requires the capacity of withstanding lateral thrust and the weight of the wind turbine. Three basic models exist -- fixed guyed, tilt-up and freestanding. Fixed-guyed towers look like those associated with radio antennas. The structure requires lifting it into place or a fixed position. At least three sets of guy wires, which have a radius equal to 50 to 80 percent of the tower's height, hold the tower in position. The most popular version comes in 10- or 20-foot triangular lattice sections that bolt together.

  Tilt-up towers eliminate the need to climb the structure, but require plenty of clear, open space. Often made of tubular steel, the structure consists of a tower pole, a gin pole and guy wires, and has a maximum height of 130 feet. The gin pole functions as a lever that enables the operator to raise and lower the tower.

  The most expensive option of the three, freestanding towers, do not require guy wires. A combination of steel and concrete keeps the structure in place.

  Freestanding towers come in three-legged styles that resemble the Eiffel tower. The other choice consists of a large single tube and is similar to commercial-grade towers. Wind towers need grounding to protect components from lightning damage.

Turbine

• The most common turbine, or generator, has an upwind design. This configuration requires installation of the blades on the side of the tower facing the wind. This design also attaches magnet alternators to the blades. The typical design has three blades. Installers tilt the blades of small wind turbines up or sideways to provide protection from high winds. Wires attached to the turbine carry the generated electricity down to the ground.

Brake

• This device shuts the turbine down for repairs or in case of emergency. Generally, wind turbines have either a dynamic or a mechanical braking system. Dynamic braking operates by a switch at the base or in the building, which shorts out the three electrical phases and stops the system. The mechanical braking system employs a disc or drum brake that the system activates by a winch located at the bottom of the tower. Another mechanical choice uses a furling that maneuvers the turbine's rotors away from the wind. Mechanical methods offer a more reliable braking system.

Battery Bank

• A battery bank makes it possible for the system to work during periods of low wind for buildings not connected to the electrical grid. This component consists of a number of batteries wired together that store energy. Some systems that work in the grid offer backup power for necessary electrical loads during blackouts. Many systems keep a household powered for three days. Lead-acid batteries are the most popular and only require replenishment with distilled water. Sealed absorbent glass mat batteries do not require maintenance; they are used for wind systems connected to the grid. Use sealed gel-cell batteries for installation in unheated spaces.