Strictly
speaking, wind power is also a form of solar power. As
the surface of the earth gets heated up with the sun’s
rays, different areas behave differently. For example,
the land mass warms up faster than the sea and the
stratum of air on top of it goes up, becoming rarified.
Cool condensed air from the sea rushes in to fill the
void, creating wind. In other words, wind blows on
account of the varying degree of worming up of the
earth’s surface and wind power is the kinetic
energy generated on account of this.
Wind
power generation, as we can see, depends on this
kinetic energy and the wind turbine is the equipment
that converts this kinetic energy in the wind into
mechanical energy. When this mechanical energy is
applied to a pump, it lifts water; applied to a grinder,
it grinds the wheat to form flour. When coupled to an
electricity generator, the mechanical energy is
converted to electricity.
Not
unlike the value of prime real estate property that
greatly relies on its location, wind power generation
depends a lot on its “site”. Unless the right ‘site’ is
utilized, wind power energy is likely to go haywire. An
appropriate site is one where strong wind is available
all through the year; no hills or tall trees create any
obstruction to free flow of wind and wind direction
remains more or less same all along. These prerequisites
are necessary for a wind power generation system to
remain effective all the year round. Also significant is
the speed of the wind blowing through the “site” which
should be around 13 mph.
Wind
generators act on the power of the wind. Their extra
long blades or rotors catch the wind as it hits them ad
they start spinning. This spinning movement, similar to
a hydroelectric system, is transformed into electrical
energy produced by a generator coupled to it. However,
the quantum of power transferred to a wind turbine
remains directly proportional to the area that is swept
by the rotor, the cube of the wind speed and the density
of the prevailing wind.
Wind
turbines that are involved in wind power generation are
usually of two distinctive types – (a) turbines that
rotate around a horizontal axis and (b) that do so in a
vertical axis, although the earlier types are more
commonly used. The HAWT or Horizontal axis Wind Power
Turbines are mounted on top the tower along with its
main rotor and the electrical generator. They are
pointed into the wind and may have a wind sensor coupled
with a servo motor for change of direction. They are
also equipped with a gearbox for changing the slow
rotation of the rotor or the blades into a faster
rotation suitable for the electrical generator.
Contemporary wind turbines come with self-adjusted
gears, eliminating the need for the heavy gearbox. The
HAWT turbines are usually pointed upwind to catch the
turbulence which is produced behind the tower while the
turbine blades are purposely placed further away from
the tower as also somewhat tilted to avoid accidental
contact with the tower.
Apart
from the HAWT turbines described above, downwind
turbines are also in use since these turbines do not
require nay additional mechanism to keep them in line
with the wind. Also, their blades are more resilient
than the upwind types, thus allowing them to adapt to
the occasional high winds encountered by
them.
It
is indeed very heartening to hear that a recent movement
in the United States in favor of more utilization of
wind power generation there is gaining ground where
all nations are likely to endorse; particularly in the
light of shortage of fossil fuel and increasing
Greenhouse effect. In fact, wind power generation seems
to be best solution to power shortages that affect most
countries that either do not believe in nuclear power
generation or are scared of likely spillage that had
created havoc in
