An offshore wind power system is described that consists of wind driven electrical dc generators mounted on floating towers in offshore waters. The output from the generators supplies underwater electrolyzer stations in which water is converted into hydrogen and oxygen. The hydrogen is piped to shore for conversion to electricity in fuel cell stations. It is estimated that this system can produce 159 x 10 to the ninth power kilowatt-hours per year. It is concluded that solar energy - and that includes wind energy - is the only way out of the US energy dilemma in the not too distant future

Heronemus, W.

English

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A PROPOSED NATIONAL WIND POWER R&D PROGRAM
William Heronemus
University of Massachusetts
Amherst, Massachusetts
My interest in wind power began back in 1970 when a group at the
University of Massachusetts was studying a proposed increase in the elec-
trical generation system for the Connecticut River Valley. In other
parts of New England others were concerned about the problem of how to
meet the increasing energy demand without causing serious ecological
damage to the New England environment. These studies led to a University
of Massachusetts proposal to investigate a national network of pollution-
free energy resources - the wind being one of them.
As a member on the NSF/NASA Solar Energy Panel, my involvement with
wind power increased. It was clear that a comparison of the energy poten-
tial of the different methods was needed. So, I decided to evaluate the
potential of wind power using one totally wind-driven system. The objec-
tive was to calculate the cost of energy delivered to the customer on
demand in New England and to compare this with the cost of energy from
systems that were being planned at the time. Meanwhile, the cost of
electricity was increasing from 28.2 mils per kilowatt-hour in 1968 to
32 mils per kilowatt-hour.
The system I chose to analyze was the "off-shore wind-power system,"
which consisted of wind-driven electrical dc generators mounted on float-
ing towers in the waters off the coast of New England where the winds are
high. The output from the generators supplied underwater electrolyzer
stations in which water was converted to hydrogen and oxygen. The hydrogen
would be piped to shore where it would be converted to electricity in fuel
cell stations.
With this system, it was estimated that 159x10^  kilowatt-hours per
year could be produced at an average annual revenue somewhat higher than
the 28.2 mils per kilowatt-hour of 1968. Even though the estimated price
was higher, the absence of the pollution that would result from fusion-
combustion processes was a benefit that was worth the added cost. This
fact - the reduced pollution resulting from wind power - and some deeper
thinking led me to the conclusion that solar energy (includes wind energy)
is the only way out of the nation's energy (and pollution) dilemma in the
not too distant future. The sooner the nation starts using solar and wind
energy, the better off everyone will be. There are several reasons for
this:
(1) We have been converting matter into heat at an ever increasing
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rate and we may be close to the time when the temperature of the earth is
going to start increasing.
(2) The coal, gas, and oil that are left stored in the Earth are
among the most valuable fossil resources that nature provided for man.
It is a crime against mankind to burn any of it.
(3) I don't believe that the U.S. chosen alternative to fossil fuel,
namely, nuclear power, is proper. The nation is headed for very grave
trouble with that alternative, a major part of it being economic. The
costs of energy have risen dramatically in three years and will continue
to rise. These then are the reasons I believe the nation needs a national
wind-power program.
The major conclusions of my wind energy study are
(1) The wind is an enormous source of power, but we must go where
it is, namely, high up, over 500 feet above the ground, to get it.
(2) It is incorrect to view and to cost out wind-powered systems
solely as fuel savers. A self-contained storage system is needed, and
power should be offered for sale on demand. The costs should be made on
that basis.
The national wind-energy program I envision should consist of three
general programs:
(1) A technology program whose objectives would be to improve the
performance of components, reduce their costs, increase their life, and
develop new concepts.
(2) A resource assessment program aimed at determining the energy
potential of the nation's wind, the most suitable sites for wind power
systems, and the effects of the wind systems on the local weather.
(3) A production plan program with the objective of using the
nation's tremendous productive capacity to produce at reasonable costs
the large number of wind power plants that are going to be needed.
In addition, an assessment should be made of the social, political,
and legal problems associated with wind power.
The implementation of the wind energy program is also an important
part of the overall program. One possibility, for example, is to suspend
large numbers of small wind-generator units on cables like suspension
bridges, or on other types of very tall towers.
In conclusion, my studies suggest that wind-powered energy systems
have the greatest chance of being used to supply an important portion of
the U.S. energy need in the near future at costs that are competitive
with other available systems.
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DISCUSSION
COMMENT: I don't think the professor has left us any questions really to
ask. .1 am absolutely with him, really. If we look at the world as a
whole and at the future of mankind, we must look more than 50 years ahead.
(And mankind usually doesn't look more than 5 ahead.) I see a future in
which our reserves are so low and our pollution levels are so high that
the sort of life that is left is not the sort of thing that I want for
my children, grandchildren, or greatgrandchildren. If we don't want that
to happen, obviously we've got to do something now. Whether windpower is
really the answer I don't know. The professor is a slightly more imagina-
tive man than I, and I see perhaps more barriers than he does. But I am
entirely with him, that wind power is one of the energy methods that we
should develop now and as hard as we can.
Q: What is the relative height above ground level that you are contem-
plating these suspended windmills, and what logistics problems you
might envision in a reasonably congested land area like the North-
eastern corner of the United States? I could easily foresee a
machine like this being used in Canada and I can see it in some of
our uninhabited islands, but I really wonder, with people's addiction
to small airplanes, glider clubs, et cetera, what legal problems you
might see, in your immediate vicinity?
A: Well, let me take that last thing first. If we do have problems with
small aircraft and gliders, then perhaps it's time that we make that
choice. We shouldn't ignore these choices any more, and just because
the FAA has allowed the small plane pilot certain privileges over the
years is no reason why that has to continue. Now, that is the way I
feel.
As for the sizes of mills or machines I studied, the system I put
together for the off-shore wind-power system was based on two sizes
of machines, because they were available to me: a 200-foot-diameter
machine and a 60-foot-diameter machine. I copied the New York Uni-
versity report and was very happy to have their results. As I said,
though, I have since come to the conclusion that in much of the
United States smaller windmills will do. As a matter of fact, I
promised a Senator from Wisconsin a study that is now a couple months
late (but I'll get to him). In that study I've been looking at wind
power supply in Wisconsin. Perhaps I can answer your question in
that context.
On the north-south running highways, which run about 20 miles apart
in Northern Wisconsin from Green Bay north on through upper Michigan,
significant wind energy could be extracted using wind generators sus-
pended over the highways. It is just as straightforward to talk
about north-south wind barrages located over the woodlands between
the highways. In this kind of wind barrage the axis height of the
lowest' machine would be 100 feet. We could suspend large numbers of
wind generators in a suspension system whose towers would rise to
some 600 feet. They would be, perhaps, cage-mast type towers with a
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bottom so configured that they could straddle the highways. The span
would be half a mile. The upper wires would drop from 600 to 300
feet. Now, on those wires we would suspend groups of vertical axes.
Each axis, capable of turning to face the wind, would in turn carry
the structural framework on which many machines, about 32 feet in
diameter, would be installed - 20 kilowatt units. (Mr. Noel probably
feels that he has made a convert. And I think he has!)
Q: Obviously you studied the Russian work that was done many, many years
ago on that same thing. What is your opinion of that?
A: I think the Russians have done some very excellent work in wind power,
but they aren't doing much of anything now. At least the last two to
whom I spoke simply ignored it or wouldn't discuss it with us. They
said it was entirely too old-fashioned for the Russians.
Q: They had looked at the grid system approach, hadn't they?
A: Yes, they had. In fact we could use structural grids. A very inter-
esting study to make would be to go back to Grandpa's Knob and that
design of a 175-foot-diameter machine (which I thought was magnifi-
cent) , and substitute for it an array of 100 32-foot-diameter wind
generators, each of 20-kilowatt capacity for a total of 2 megawatts
installed capacity. This array would look somewhat like a big bill-
board, or radar mattress. They could be spaced far enough apart so
that each machine could develop its wake fully, so we wouldn't suffer
an efficiency loss there. How would this different 2-megawatt wind
generator compete? I think it would do a lot better than the 175-foot-
diameter machine did.
COMMENT: May I make a brief remark about the Russian effort? Very re-
cently I did some intensive digging, talking to people in Washington and
elsewhere about this alleged big wind power effort in Russia. Most of
the Russians just smiled and thought I was rather primitive. They pointed
out that they had built a few, but that they had so much hydroelectric
power that they could run wires anywhere in the country. They don't need
windmills.
COMMENT: I will just make an observation on the basis of the WKY towers.
There is about a M-0-percent higher wind velocity at 600 feet and about an
additional 60 percent up to about 1000 feet.
COMMENT: Putnam, I think, came out with those figures quite nicely. He
showed that you are really in the realm of diminishing returns by the
time you go much above 150 feet. But I feel that you have to say, "Okay,
so I'm in the realm of diminishing returns, but that's where the wind is.
If I want to stay below it, I'm not going to get much wind." It's like
those systems studies of fishing in the Gulf of Maine that said so con-
clusively that the most economic place to fish is in the street in front
of the fish pier! The only problem is that the fish don't know that.
COMMENT: There is one point we must remember, unless you've thought of a
new way of keeping your machines up there: The higher the tower, the more
steel or some other metal you have to use. It takes some 13 200 kilowatt-
200
hours to produce a ton of steel and 50 000 kilowatt-hours to produce a
ton of aluminum.. We shouldn't waste energy in the structure before it's
even built, there's no energy balance in that.
Q: How sensitive are your power costs in the final step of converting
hydrogen to electricity if it's done by fuel cells. What lifetime
energy have you amortized in the case of fuel cells?
A: It's quite sensitive in the case of the hydrogen fuel-cell link,
though the most expensive portion of that system is the blades of
the wind generators themselves. The second most expensive portion
was the complete system from the electrolyzer through the fuel cell.
Now, the fuel cell life I used was 15 years, and you go ahead and
whistle! I know that some of you people keep saying that Pratt &
Whitney really don't know what they're talking about. But I happen
to have been in their lab off and on for many years, and I'm quite
confident that the 15-year life is going to be achieved. In fact,
this is just one aspect of the wind power system using a hydrogen
link that I feel has a real future - all right, go ahead, shake your
head! I'm sorry!
COMMENT: I think I have to answer that. I worked in the last 15 years
in the field and I can't share their optimism that a 15-year fuel cell is
around the corner. I've seen no test data from anyone that exceeds 2 years.
A: Someone thought enough of it about 4 months ago to assign them a $90
million R & D program.
COMMENT: I understand that some of our people are going to work on it.
That's fine.
COMMENT: I would like to join him. Oklahoma State has had 10 or 12 years
experience. You must know something we do not see in the published lit-
erature. I don't think a long-life fuel cell will come around in the
next 5 to 8 years.
A: I know of one New England utility who is purchasing from Pratt &
Whitney right now a considerable number of kilowatts of hydrogen-air
fuel cells at a total cost of $185 a kilowatt, which includes re-
former. Now, I don't know the life specs, but I'm sure that it's at
least 15 years. Now that's as much as I know; you've got me in over
my eyebrows!
The most significant work in fuel cells perhaps has not been - and this
is really going to hurt - the NASA work of the last few years, but the
U.S. Navy work which created the fuel-cell power system for the deep
ocean search vehicle. Those results are not available to all of us.
COMMENT: Bill, I think you have released a flood of philosophy here,
which I think is not unwelcome. I am frequently called on to address
groups on the subject of the energy crisis and the like, and I have been
using a subtitle to my talk. Usually it's something having to do with
the resource crisis. I think it's appropriate this afternoon to mention
201
it and perhaps coin a new phrase.
What I am referring to is that in any resource pinch such as that in
which we find ourselves now, our criteria have got to change very rapidly.
The escalation of the energy crisis really took off essentially like a
rocket in about 1969. Many of us take a good deal of comfort in looking
at the average cost of energy curves. Though the average costs are up
from 1969, they are still artifically depressed by the fact that some of
the energy contracts in force today were negotiated several years ago.
If you look very carefully at the current contracts, you will see that a
cost of about 90 cents per Btu is fairly common. Those are the numbers
we should look at, not the averages.
Now, when Bill speaks of suspension via hydrogen balloon or cables or
towers, or what have you, I don't think itTs exactly pertinent to point
out that aluminum takes so many kilowatt hours per ton and steel so many.
These are one-time costs, and they can be energetically amortized.
Now, the subtitle to which I refer and which I think is appropriate today
is, "Don't worry about Mars and Venus. The question is 'Is there intel-
ligent life on Earth?'"
I would also like to add that, if we assume that our present point in
history is perhaps 5000 years removed from the first time man recorded
things by infusing them on stones, perhaps this generation has another
five thousand years. The fossil fuel era, through which we are presently
half way through and passing very rapidly, I very inelegantly refer to as
a small pimple on the rear end of history.
I think it would also be appropriate for us to ask ourselves something
to the effect that (I think the word "war criminal" was coined during the
latter stages of World War II) "Are we behaving as "resource criminals,"
because we're using it up just as fast as we please without a thought to
where it ends and what our children and their children will have to do with
when their time comes?"
COMMENT: If you are brainstorming, you can come up with all kinds of
designs for windpower plants. I could surprise you by some of the ideas.
For example, if you put a heavy rotor on a tower and put a rope on it and
drive it, it will go higher up in the air. Then, if you fix the next one
then you can put both rotors up in the air to the stratosphere.
This is just one of the hundreds of ideas that could be mentioned here.
The solution to accumulate many rotors on a system of steel ropes or some-
thing like that has been brought up by Russia and by Holland in the middle
of the twenties. Going in this direction is a market question.
Let me mention one thing, which is the best size for wind electric power.
This is an important question. If you make small ones, you can produce
them in quantity and get the advantage of a lower price by "their small
size.
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If you make big ones, you get advantages of the fewer parts and there is
somewhere a minimum of the cost, and we have to be very careful to do
this. We can calculate the minimum.
A: Doctor, I think some of your fellow engineers have designed very
distinctive wind generators. I am not sure I could contribute any-
thing.
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A proposed national wind power R and D program

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