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Tilting at Windmills
A Reading of a Wind Turbine
By
Charlotte Ebel
1
Introduction
At the Teachers as Scholars
Institute held at Princeton in
2005, Professor Michael S.
Mahoney challenged the
participants to engage in a
process that he called
“reading a machine.”
2
In the opening paragraph of his article by
that name, he quoted the title of a paper
presented by R.W. Hamming at the
International Conference on the History of
Computing in 1976:
“We would know what they
thought when they did it.”
3
What I Thought When I Did It
“That notion,” I could say, parroting
Mahoney, “took some time to
penetrate my literary instincts.”
4
It’s not that I feared objects. I have always been
comfortable with them and collected far too many of
them. I’m more mechanical than many women. I can
change a tire, fix a vacuum cleaner or a washing
machine, even open up the butterfly valve of my old
Ford Mustang when it sticks. I am not afraid to tinker
with my computer.

5
But my literary instincts were so
strong to overcome. My whole, long
career has been explicating texts,
parsing sentences, scanning poems,
analyzing statutes, “mining” judicial
opinions.
6
Words are my nuts, bolts,
transmissions, motors, governors,
pulleys, ailerons, but when it
comes to machines, my curiosity
surpasses my ken. I suppose it
would not be true curiosity if it
were not so. What I mean is this
is both my strength and my
weakness.
7
Mahoney goes on to elucidate in his
article the point that the practice of
science and the literature of science do
not necessarily coincide. He avers that
early in his career, he had “cast about
for the primary sources of technology
since the Renaissance,” a quest which
he discontinued when he realized that
“the great ideas we were seeking did
not lie in books. They lay in objects.”
8
Choosing an object was
my first task.
9
Having enjoyed a preview of the
course, I had long thought about it and
formulated the idea that I wanted to
study the Lemieux brothers early work
in film production. I later discarded the
idea, thinking, because of the
published title of the course, that we
would be obliged to choose a scientist,
inventor, or object more closely related
to American history.
10
I then thought of wind turbines since
this alternative form of energy is a topic
that has interested me for several
years. And later, when the course had
begun, a humorous aside by the
professor planted the idea that I, a
French teacher, might investigate the
guillotine.
11
So Many Ideas, So Little Time !
12
I would choose the one for which
materials were easily accessible, and
eureka! The first trip to the library
stacks produced what seemed to be
just the right books to do the “reading”
on the guillotine.
13
They practically flew off the shelf into
my hands with titles promising answers
to the central questions of the exercise.
As I perused them, the characters, the
drama, the history, the moral issues
came spilling out and flooded my mind
with scenes that I knew well. I would
undoubtedly glean some juicy details to
take back to my French classes.
14
However, as I thought of it
in the context of the “machine
readings” we had done in class, the
guillotine seemed less interesting.
Where would I find a model this side of
France? It lacked the myriad
“quotations” that even I could recognize
in the wind turbine, but would I ever be
able to attribute them all? And I had no
15
No model, and yet I had experienced wind turbines
16
It was in the summer of 1988 when my
family on the return leg of a cross-country
trip rolled from the top of a hill into the valley
of Altamont in California and there they
were, like so any sentinels.
17
We were awed by their height, enchanted by their
grace, mesmerized by their sound – a whir, a
whoosh, a blade cutting air, but not as its sharp
severance by a sword, rather like a graceful diver
cutting through the surface of the water.
18
I thought of a line in a book I used to
read the children, Gilberto and the Wind:
“Who has seen the wind? Neither you
nor I. But when the leaves blow down
the street, the wind is passing by.”
Marie Hall Ets, Gilberto and the Wind
19
No leaves on this treeless plain, but still one
knew the wind was passing by from the
rhythmical cosmic whisper of these turbines.
20
We wanted to think then that it was
the wind telling us of some magical
future when the production of
energy no longer polluted our
atmosphere but instead gave us
elegant machines that through their
rhythmic gymnastics unfurled a
stream of wind-borne electricity to
power our lives.
21
Now in this course, I ask myself how
they came to be, these turbines.
Their obvious antecedents
were the windmills.
22
What did I know of them?
23
I thought about my childhood
pinwheels.
24
I thought about . . .
my fascination with Dutch windmills
when I read Hans Brinker, or the Silver
Skates.
25
I thought about . . .
dear old Daudet
writing in his
windmill in
Provence.
26
I thought about . . .
Don Quixote
jousting with
Windmills.
27
That is what I thought when I
did this, that is …
28
. . . when I tilted with windmills,
when I tried to “read” – from an image, no less –
a wind turbine, a modern windmill.
29
The Reading
30
A wind turbine is
an impressive
structure.
31
A typical
height for a
commercial
turbine tower
is about 230
feet.
32
There is a door in the base of the tower.
The door allows access to an
interior ladder.
One may ascend the tower
from the inside to perform
maintenance.
33
At the top of the tower is
the nacelle.
It encases the
engine.
It is about the size
of a small school
bus.
34
On the front of the nacelle is the rotor.
This model has three
blades.
The blades are very smooth
so that the wind may pass
easily over them.
They are very strong so as
not to break in the wind.
They are aerodynamic in
design.
They are connected to a
shaft that turns the dynamo
inside the nacelle.

35
Here we see the enormous size and the
aeronautical design of a rotor and blades.
36
The blades
are routinely
washed to
keep them
clean. Any
cracks are
filled to
keep them
smooth.
37
Let’s look inside the nacelle.
38
39
What’s happening?
The blades scoop up the
wind and use its power to
turn the gears.
The gears make the high
speed shaft turn approx. 50x
faster than the low-speed
shaft.
The high-speed shaft turns
the dynamo to produce
electricity.
If the wind speed becomes
too fast, the controller
computer shuts down the
turbine.
A cooling mechanism keeps
the generator from
overheating while it is
working so fast.
The yaw mechanism orients
the rotor to the wind.
40
This model turbine is very
expensive and complex.
It is intended for use by a
commercial supplier, such as an
electric company. It is part of a
system.
41
These large installations are called
wind farms.
Notice that the wind turbines in this picture have lattice towers.
42
The turbines connect to a grid that
will transmit the electricity to the
consumer.
43
These high lines are part of the delivery system.
44
Some consumers, especially in
remote locations, install small wind
turbines to serve their residence
individually.
A 1,500-watt wind turbine provides this
home in Colorado with electricity. Credit:
Jim Green
Some of the documents on this page
are available as Adobe Acrobat PDFs.
Download Acrobat Reader
45
Environmental Concerns
•Birds
•Noise
•Visual
•Climate
•Land Use
46
Where’s wind energy going?
47
Reflections
On reading a
machine
48
This project has undergone
numerous transmogrifications
during the two weeks of the
Teachers as Scholars Seminar.
Each day Aeolus seemed to
release research winds from a
different direction. I sometimes
doubted the ability of my brain
to yaw sufficiently in the right
direction.
49
On the last day of class
before presentations, two remarks
collided with a scene I had
observed on the previous day’s
field trip to the National Museum
of History and created a spark that
illuminated a creed I have long
held.
50
The first remark occurred when we were
discussing the history of the computer.
After detailing how memory systems
were created, the professor commented
that this mimicked some human brain
functions, and he quoted Chomsky on the
mysteries of language learning and the
many cognitive secrets that lie embedded
in our universal grammar. He concluded
by observing that the human brain is
51
the greatest machine of all.
The field trip to the National
Museum of History intervened between
the first and second remark. We were
looking at an early machine. Someone
identified a piston. Another remarked
how the heavy leather belt moved from
one wheel to another to shift gears. The
professor stitched together our random
52
observations on mechanisms and
purpose, explaining the full operation
of the machine . . ., but I was having
trouble focusing on the discussion.
My attention was diverted to “reading
the machine” I saw in the top, back
corner of the exhibit area: a video
camera, its red, glowing eye trained on
the spectator positions where we were
standing.
53
The second remark had a touching
wistfulness. It grew out of a
discussion between the professor and a
student, a continuation actually, of our
attention to the question of why
women are not more successful as
computer programmers. The
comments were touching on
interrupted careers, day care,
maternity/paternity leave. It’s too bad,
54
said the professor, and I paraphrase,
that we haven’t been more creative,
more successful at solving this
problem in a way that is fair to all,
because, after all, raising our
children is probably the most
important thing many of us ever do.
These molecules of conversation
kept bonding together as I sat for a
while after class on a bench outside.
55
Human brain = greatest machine
I wanted to stand before you today and
say, “Here is my machine. Read it.” I
thought of this together with the
statement from Marx that the professor
likes to quote to the effect that when
the new first appears, it appears in the
guise of the old. When one grasps
what is new it takes a form more
appropriate to it.
56
Our children are like us until they
realize what is new and unique
about themselves and then many
of our traits – and one hopes the
bad ones – disappear. Are we able
to read what is new and improved
about each one’s machine?
57
We have all of us often
asserted in class that we will never
afterwards look at objects the
same. We shall always be
analyzing, probing, touching them
and asking: For what purpose are
they made? Who is the intended
user? But just as I shall be reading
machines, I shall also look at my
fellow man and woman, especially
58
my students, analytically, searchingly,
trying to read each “machine”, and I shall,
through my actions, forever be imploring
the parents of the children entrusted to
me: “Read my machine at work. Observe
all its moving parts. See how I am
forever shifting gears, turning dynamos,
transmitting energy to light up what is
unique and glorious in this child.” After
all, it’s our most important work!
59
Mais, si tu m’apprivoises, nous
aurons besoin l’un de l’autre. Tu
seras pour moi unique au monde.
Je serai pour toi unique au
monde… St. Exupery,Le Petit Prince (45)
60
The following are links to some excellent
sites for teachers and students:
http://www.windpower.org/
en/kids/index.htm?d=1
http://www.siue.edu/EDUCATIO
N/AAM/lesson/parker/AAM%20
webpage/WINDMILL/windmill%
20lesson%20plan.htm
61