Student
Name:
___________________________
Lab
Partner:
______________________________
Lesson
2:
The
Power
in
the
Wind
In
Lesson
1
you
compared
the
geographical
position,
land
use
patterns,
and
topography
of
Roscoe,
Texas
to
locations
in
North
Carolina.
Although
wind
speed
data
was
used
to
make
this
comparison,
the
WindNavigator
software
provided
no
information
about
the
direction
from
which
the
wind
blows
or
how
often
the
wind
blows
in
those
locations.
Wind
as
a
source
of
energy
is
not
sufficient
to
provide
continuous
electricity
because
even
in
the
best
location
wind
is
variable.
If
there
is
no
wind
blowing
no
energy
can
be
generated.
So,
the
amount
of
power
that
can
be
harvested
from
the
wind
will
depend
on
wind
frequency
and
wind
direction
(since
wind
turbines
are
most
efficient
when
facing
into
the
wind).
WIND
FINGERPRINTS
‐
Wind
Rose
Wind
roses
are
circular,
graphical
displays
of
wind
speed,
direction,
and
frequency
based
on
a
simple
compass
rose.
Wind
direction
is
shown
by
the
length
of
a
line
representing
a
number
of
wind
collection
events.
The
length
of
the
line
from
the
outer
circle
to
the
center
of
the
rose
shows
the
percentage
of
total
wind
measurements
where
the
wind
blows
from
that
compass
direction
–
incorporating
both
frequency
and
direction
data.
Wind
speeds
are
shown
using
a
number
of
different
techniques.
In
order
to
make
a
wind
rose
for
winds
in
your
area,
you
will
need
wind
speed,
wind
direction
and
wind
frequency
data
for
your
chosen
location.
For
weather
stations
in
North
Carolina
this
data
is
archived
by
the
State
Climate
Office
of
North
Carolina
at:
http://www.nc‐climate.ncsu.edu/cronos/
Your
teacher
will
supply
you
with
either
an
Excel
spreadsheet
containing
this
data
or
a
hard
copy
of
the
data.
It
will
show
average
monthly
wind
speed
and
wind
direction
for
the
average
wind
speed.
You
will
use
this
data
to
calculate:
1.
Percent
frequency
of
wind
speed
in
each
of
the
eight
compass
directions
moving
clockwise
around
the
compass
rose
starting
at
N,
NE,
E,
SE,
S,
SW,
W
and
NW.
•
Count
up
the
total
number
of
data
points
and
record
the
count.
•
Count
and
sum
up
the
total
number
of
data
points
with
wind
blowing
from
a
certain
direction
(all
the
data
with
N
as
the
wind
direction
and
record
the
count.
•
Divide
the
total
number
of
data
points
showing
the
wind
blowing
from
a
particular
direction
and
divide
that
number
by
the
total
number
of
data
points
reported
(first
step
above).
Then
multiply
the
result
by
100
to
obtain
the
%
frequency
blowing
from
that
direction
and
record
the
%
frequency.
Repeat
this
calculation
for
each
of
the
8
possible
wind
directions.
•
Calculate
the
average
wind
speed
for
all
data
points
blowing
from
that
particular
direction
(for
example
N)
and
repeat
this
calculation
for
each
of
the
8
possible
wind
directions
and
record
the
results.
•
When
you
have
finished
these
calculations
you
should
be
able
to
complete
the
following
table:
1
Student
Name:
___________________________
Lab
Partner:
______________________________
Table
of
wind
frequencies
and
directions
Compass
direction
wind
blows
from
%
Frequency
from
that
direction
Average
wind
speed
from
that
direction
North
North
East
East
South
East
South
South
West
West
North
West
2.
Once
you
have
completed
the
calculation
of
wind
frequency
in
each
of
these
directions,
open
Internet
Explorer
as
your
browser
and
enter
the
URL
http://guidedtour.windpower.org/en/tour/wres/roseplot.htm
Your
screen
should
look
like
Figure
1.
below.
3.
Make
sure
that
the
“Sectors”
tag
is
set
to
“8”
and
then
enter
the
data
from
the
Table
1
into
the
two
columns
with
their
headings
circles
in
red
as
shown
in
the
figure
below.
If
your
data
shows
data
for
more
than
8
directions
(for
example,
North
North
East)
treat
the
triple
compass
directions
(North
North
_______
)
as
if
they
were
double
compass
directions
by
dropping
the
first
direction
(for
example
North
North
East
would
become
North
East).
If
you
have
no
wind
a
particular
direction
be
sure
to
put
“0”
in
the
%
frequency
space
and
the
wind
speed
space
so
that
each
of
the
8
columns
is
filled
with
data
in
the
clockwise
order
from
North
to
North
East
to
East
etc.
2
Student
Name:
___________________________
Lab
Partner:
______________________________
4.
After
you
have
entered
the
8
data
points
make
sure
that
all
of
the
boxes
below
your
8
data
points
have
“0”
entered
in
them.
5.
Click
on
“Plot”
near
the
bottom
of
the
page.
The
image
of
the
wind
rose
should
appear
on
your
screen
in
a
separate
window.
Move
your
cursor
so
that
it
is
somewhere
on
the
image
and
then
press
<Ctrl>
and
<C>
simultaneously.
If
you
have
a
PC
computer
you
will
need
to
open
up
Paint
or
some
other
drawing
program
and
once
it
is
open
simultaneously
hold
down
the
<Ctrl>
and
<V>
keys.
The
wind
rose
image
should
appear
in
Paint.
6.
Use
the
Paint
tools
at
left
to
insert
the
main
compass
directions
in
the
right
place
on
the
drawing
(N,
E,
S,
W).
Then
label
the
%
frequency
represented
by
the
outer
circle
(it
will
be
equal
to
the
largest
percent
frequency
recorded
in
your
data)
and
the
inner
circle
which
will
be
½
of
the
outer
circle
value.
Put
a
title
and
your
name
on
the
image
too.
7.
To
save
the
image,
choose
“File”
from
the
upper
left
hand
corner
of
the
page
and
then
from
the
drop
down
menu
choose
“Save
As”.
In
the
dialog
box
enter
a
name
for
your
wind
rose
and
in
the
next
box
change
the
“Save
as
type”
box
to
“GIF
(*.GIF)”
to
your
desk
top.
8.
In
the
space
provided
below
use
“Insert”
to
select
and
place
the
image
wind
rose.
Wind
Rose:
9.
Summarize
what
the
wind
rose
you
have
created
means.
What
is
it
telling
you
about
the
potential
of
your
area
for
wind
power?
You
may
want
to
refer
to
http://guidedtour.windpower.org/en/tour/wres/rose.htm
to
get
a
better
understanding
of
this
style
of
3
Student
Name:
___________________________
Lab
Partner:
______________________________
wind
rose.
It
is
a
different,
but
in
many
ways
similar,
type
of
graphical
display
to
the
wind
roses
you
have
been
looking
at.
4