How Do Wind Turbines Work?
How wind turbines work can be explained as a conversion of kinetic
energy (wind) to mechanic energy (turbine). Wind energy is essentially
a form of solar energy since it is the sun that heats unevenly
the Earth's surface causing the breeze to blow.
There are two basic types of wind generators including the horizontal
axis wind turbine and the vertical
axis wind turbine. Understandably one turns on a horizontal
axis (or axel) and the other one upon a vertical axis (or axel).
Each type of wind turbine works in similar fashion. Basically,
the wind blows past the wind generator blades or rotors causing
a low pressure system on the trailing edge of the blades similar
to a wing of an airplane. Utility scale wind turbine blades may
need a wind speed of 10 mph or more to start turning while residential
wind turbines may start rotating at speeds of 7 mph or less.
Smaller wind turbines will use a tail fan and larger devices
will use computerized tracking to keep the blades pointing into
the wind for optimal efficiency. Utility wind turbine blades are
connected to shafts, gears, generators and electrical control
systems. These systems then interface with high-voltage transformers
and then to the grid.
Small wind turbines such as those used at residences usually
have the blades connected to a DC generator, power inverter, AC
generator and bank of batteries. The home wind turbine is used
to power the batteries, which in turn power the residence. An
electrical contractor can tie in the home wind generator to the
grid if desired.
How wind turbines work efficiently have to do with the size and
shape of the rotors, the location of the turbine including geography
and height and other basic mechanics that either cause more drag
or less drag on the system. Many assume that the old style windmill
with many blades is more efficient because of the number of rotors.
But, the number of rotors can actually add more drag, more weight
and get in the way of wind flowing through the blade area. Two
or three bladed turbines are most popular now days because of
more thrust and less wind resistance.
One of the main factors that contribute to how wind turbines
work is the kind of electromagnetic system that is used to generate
electricity. The wind turbine blades are usually tied into something
akin to the alternator in one's car.
The alternator works because many loops of copper wire spin around
at high speeds around an iron core, producing an electromagnetic
current (electricity). The kind of electromagnetic induction can
vary depending upon the size of the wind turbine and the manufacturer's
specifications and design.
How wind turbines work has changed over the years. The history
of wind power starts with these renewable energy devices being
used to grind grains and pump water. Over the years, the need
to use wind turbines for electrical generation has come to the
forefront and which is why so much development is taking place
right now.
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