WIND

WIND
WHAT
IS wind
WINDenergy?
ENERGY?
What is
Wind is air on the move. Each air molecule has
Wind energy
generated
harnessing
kinetic
energyisbecause
it is by
moving.
The
energy
of the
the combined
kinetic
the wind
andwind
is theisworld’s
fastest growing
energy
of
all
of
the
molecules.
The
wind
is a
energy source. It’s becoming more important
free
and renewable
sourcetoofuse
energy,
it is
for electricity
companies
wind and
energy
the
world’s
fastest-growing
as it’s
a renewable
and free electricity
resource.
resource.
How is electricity generated from wind?
HOW IS ELECTRICITY GENERATED FROM
Electricity companies harness wind energy
WIND?
with wind turbines. When the wind flows
Electricity companies catch the energy of the
past using
the turbine’s
rotor blades,
thefarm’
blades
wind
wind turbines.
A ‘wind
will
turn
and
convert
the
wind
energy
into
kinetic
often contain many identical turbines. When
energy.
energy
spins
rotor inside
the
windThis
flows
through
theablades
of a
a
generator
where
the
kinetic
energy
turbine, they rotate and spin, poweringisa rotor
converted
into electrical
energy. electricity.
inside
a generator
and producing
Each turbine works independently. The
Once the wind energy is converted into
electricity flows through cables in the turbine,
electricity,
flows and
through
cables
flows
downthe
theelectricity
turbine tower
combines
in the
theother
turbine
tower
to
with
theturbine,
energy down
from the
wind
turbines
with
thebefore
outputentering
from thethe
other
wind
inconnect
the wind
farm
local
turbines innetwork
the wind
before entering
local
electricity
orfarm
the national
grid, which
electricity
networks.
The
greater the wind
provides
power
to New
Zealand.
speed, the more electrical energy generated.
WHAT’S INSIDE A WIND TURBINE?
You’llwind
usually
see more
than
wind
Each
turbine
has four
keyone
parts.
turbine working to generate electricity – this
is called a wind farm. All the wind turbines in
Foundation
The
foundation
holds
the turbine in
place
in
a wind
farm work
independently.
The
output
the
ground.
A wind
turbine has
to have
a
of each
turbine
is combined
before
it enters
strong
foundation
to
handle
strong
winds
and
a local electricity network or the National Grid
support the overall height and the length of
What’s
inside a wind turbine?
the
blades.
Each wind turbine has four key parts:
Foundation: The foundation holds the turbine
in place in the ground. A wind turbine has to
Tower
Generation equipment is kept in the tower.
have
a strong
foundation
to and
withstand
strong
The tower
raises
the blades
generation
winds
and support
the overall
heightinto
andthe
the
equipment
high above
the ground
smoother,
stronger
wind
currents.
Access
to
length of the rotor blades.
the nacelle and rotor is through the tower.
Tower: Generation equipment is kept in
the
tower. The tower raises the blades and
Nacelle
generation
above
the ground
The nacelleequipment
is the hearthigh
of the
turbine,
where
into
the smoother,
stronger
wind are
currents.
the generator,
gearbox
and rotor
held.
Access
to the nacelle
andnacelle
rotor isisthrough
The generator
inside the
used to
convert
the wind energy into electrical
the
tower.
energy.
Nacelle: The nacelle is the heart of the
turbine,
Blades where the generator, gearbox
and
drive train
are
held.that
Mostturbine
wind turbines
haveparts
three
blades
The
generatortoinside
the nacelle
is used
are attached
the rotor.
The longer
theto
convert
the the
wind
energy
blades and
faster
theinto
windkinetic
speed,energy
the
and
then
electrical
energy.
higher
theinto
possible
output
power. The blades
are tested thoroughly to ensure that they will
Rotor:
wind severe
turbines
have three
blades
handleMost
the most
weather
conditions
that
are attached
to the
rotor. Blades in wind
expected
at the wind
farm.
turbines are tested thoroughly to ensure
that they will stand up to the most severe
weather conditions.
Are wind turbines safe to use?
Each wind turbine has an internal computer
system that monitors the direction and speed
of the wind, and allows it to automatically set
itself to operate at a safe level. If there is any
damage to the turbine due to overcapacity
(wind speed and strength), the turbines shut
down automatically.
RENEWABLE ENERGY AT HAU NUI WIND FARM, WAIRARAPA
SOURCE: GENESIS ENERGY
What are the advantages of wind energy?
The greatest benefit of using wind energy is
This work is copyright. The copying, adapting or issuing of this work to the public on a non-profit basis is welcome. No other use of this work is permitted without the prior consent of the
copyright holder. From ElectroCity www.electrocity.co.nz © Genesis Energy 2010.
ARE WIND TURBINES SAFE?
that
generates
electricity
withoutcomputer
emitting
Eachitwind
turbine
has an internal
greenhouse
Wind
hasand
little
system that gases.
monitors
theenergy
direction
effect
this automatically
is because:
speedon
of the
the environment,
wind. The system
sets itself to operate at a safe level. If the
• wind energy is a renewa ble res ource,
wind speed exceeds a safe level or if there is
sodamage
it can never
run
out the computer will
any
to the
turbine,
•shut
thethe
re aturbine
re no em
is s ion
s when generusually
a ting
down
automatically,
from
windinto the wind so they
byelectricity
twisting the
blades
don’t turn the turbine.
Wind farms lessen the need for us to use
fossil fuels to generate electricity, which helps
WHAT ARE THE ADVANTAGES OF WIND
to reduce greenhouse gas emissions.
ENERGY
What
areenergy
the disadvantages
of wind
energy?
Wind
is a renewable
resource,
so it
will never
runenergy
out. is a great
Although
wind
Wind energy has little direct effect on the
environmentally friendly option to generate
environment, as there are no greenhouse
electricity, a lot of turbines are needed in one
gas or heat emissions or other pollutants.
place
in order
to generate
power forof up to
Modern
turbines
with capacities
communities
use.wind
Somefarms
people
think they
1 MW meantothat
of between
100
have
a negative
visual
impactThese
on theare
and
150 MW are
practical.
landscape
and are
comparable
withnoisy.
many existing hydro and
geothermal power stations in New Zealand.
How
is windcan
energy
used in and
Newrepaired
Zealand?
Turbines
be serviced
individually
without
the need
close down
Wind
energy plays
a useful
role intoenergy
an entire wind farm.
generation for New Zealand. There are
Once a wind farm has been constructed, the
currently
seven
wind
farms
in operation
in
land can
still be
used
for other
purposes,
New
Zealand.
Combined,
these wind farms
such
as farming
or agriculture.
have a capacity of 170MW, which will
produce
enough
energy for aboutOF
75,000
WHAT ARE
THE DISADVANTAGES
WIND
average
New
Zealand
households.
ENERGY?
Wind farms tend to be highly visible and cover
large areas, usually on ridges or hilltops. Some
people dislike seeing large numbers of turbines
on the horizon and some complain that they
are noisy.
HOW IS WIND ENERGY USED IN NEW ZEALAND?
Wind energy plays a significant, growing role in
energy generation for New Zealand. By the end
of 2009, there were seven main wind farms in
operation in New Zealand. Combined, these
wind farms have a capacity of nearly 500 MW.
In addition, there are several smaller wind farms
and individual turbines, and more wind farms
are under construction.
ACTIVITIES
ACTIVITY ONE
Divide the class into groups. Assign each group
one of the seven main wind farms in operation in
New Zealand.
Hau Nui
Horseshoe Bend
Tararua
Te Āpiti
Te Rere Hau
West Wind
White Hill
The teacher displays a large map of New Zealand
on the wall and labels the wind farms. Groups
research their assigned wind farm, find out why
the site was chosen and present this information
back to the class. For example:
Hau Nui wind farm, south-east of Martinborough
in the Wairarapa, is ideally located to capture the
wind currents that are funnelled and accelerated
through the nearby Cook Strait and over the
Rimutaka Ranges. The wind farm has 15 turbines
and a capacity of 8.65 MW, which provides
enough energy for around 4,200 homes in the
Martinborough area and, depending on demands
and output, as far north as Greytown.
ACTIVITY TWO
WIND ENERGY QUIZ
Students answer the following questions.
How long have wind turbines been
available as an energy source?
Before wind turbines were invented,
how did people use wind to generate
electricity?
Why is wind energy a good choice for
environmental management?
What is kinetic energy?
ACTIVITY THREE
BUILD A MODEL WIND TURBINE
Here are some websites and publications
showing how to build devices that use the
energy of the wind.
Make an Anemometer (Energy Quest –
California Energy Commission).
An activity that shows students how to
make an anemometer, which is a device
that tells you how fast the wind is
blowing.
http://www.energyquest.ca.gov/projects/
anemometer.html
Make Your Own Wind Winch (Solar
Schools)
http://www.solarschools.net/resources/p
df/make%20your%20own%20wind%20w
inch.pdf
Ministry of Education. 2004. ‘Windmills
and Waterwheels’. Building Science
Concepts (Book 54). Wellington: Learning
Media.
SUPPORTING RESOURCES
-
New Zealand Wind Energy Association: www.windenergy.org.nz
Ministry of Economic Development: www.med.govt.nz
Energy Efficiency and Conservation Authority: www.eeca.govt.nz
Genesis Energy: www.genesisenergy.co.nz
`