Wind farms offer more power,
possible problems
POSTED: 2:11 p.m. EDT, May 3, 2007
WASHINGTON
(AP) -- Wind farms could generate as much as 7 percent of
The
towers appear most dangerous to night-migrating songbirds, bats and some
hunting birds such as hawks and eagles. The risk is not well enough known to
draw conclusions, a panel of the National Research Council said Thursday in a
study requested by Congress.
"The
human impacts of wind farms can be both positive and negative," said Paul
G. Risser, chairman of the committee that prepared
the report.
Clearly
the farms provide jobs and in some cases they can even be a recreational
attraction, he said. But there can also be an effect on property values and
reflections off the rotor blades can be distracting to some people, said Risser, current acting director of the Smithsonian's
National Museum of Natural History.
Wind
has powered sailing ships for thousands of years and has long been important to
turn windmills that move water and grind grain. Only in recent years had the
potential of the wind to generate electricity been tapped.
Wind
farms generate electricity by using the wind to turn giant blades that rotate
turbines to make power. The blades have diameters ranging from 230 feet to 295
feet and are mounted on towers between 97 feet and 295 feet tall. Some farms
contain hundreds of towers. The one at
Growing
from almost nothing in 1980, wind powered turbines generated 11,605 megawatts
of electricity in the
Wind
farms now operate in 36 states. The report says estimates are that this source
could generate from 2 percent to 7 percent of the nation's electricity within
15 years.
"There
is a great diversity of opinion on how much there is going to be a ramping up
of wind energy," said report co-author Mary English of the
By
reducing the need to generate electricity from by burning fossil fuels the
turbines have been welcomed as a boon to the environment. Others worry about
the danger to birds and bats, impacts on wildlife habitat and what some see as
a blight on the scenery.
Overall,
the report noted, the benefits of wind-energy development such as reductions in
air pollutants benefit wide areas, while the environmental costs, such as
effects on the ecology and increased mortality of birds and bats, occur
locally.
The
Research Council, as arm of the National Academy of Sciences, concluded that:
By
the year 2020 wind generators could offset as much as 4.5 percent of emissions
of the greenhouse gas carbon dioxide from electricity production. The savings
would be less in the mid-Atlantic states where there
is less regular wind.
Wind
generation in the mid-Atlantic highlands -- elevated regions of
In
the mid-Atlantic highlands, preliminary studies indicate that more bats are
killed than expected based on experience with bats in other regions. There is
not enough information to determine whether the number of bats killed will have
overall effects on populations. However, there has been a region-wide decline
in several species of bats in the eastern states, so the possibility of
population effects is significant.
Turbines
placed on ridges, as many are in the mid-Atlantic highlands, appear to have a
higher probability of causing bat fatalities than those at many other sites
At
current levels of use, there is no evidence that fatalities caused by wind
turbines result in measurable demographic changes to bird populations
nationwide, with the possible exception of raptor fatalities in the Altamont
Pass area. However, data are lacking for a many facilities.
While
aesthetic concerns often are the most heard about proposed wind-energy
projects, few decision processes adequately address them.
Other
potential human impacts include effects on cultural resources such as historic,
sacred, archaeological and recreation sites and the potential for
electromagnetic interference with television and radio broadcasting, cellular
phones and radar.
The
Treating a symptom
rather than disease 4
Orlando
By
Michael Zimmerman
Scientific
experts on a high-level panel have come up with what they think might be a
dramatic cure for the greenhouse effect.
Unfortunately, while their solution is in keeping with a basic law of
ecology, their idea runs afoul of an equally basic law of medicine.
The
experts, a panel of top scientists gathered by the National Research Council
(NRC), have endorsed a plan to fertilize the planet's oceans with iron. After all, iron is supposed to promote the
growth of tiny marine algae known as phytoplankton. Phytoplankton, like all
green plants, take up carbon dioxide, one of the most troublesome
greenhouse gases. and release oxygen. So the thought is that a dramatic increase in
phytoplankton will lead to the removal from the atmosphere of a large
percentage of the offending carbon dioxide.
Why
iron? As every gardener knows, and as I
teach my introductory ecology students very early on, the answer is quite
simple. In 1840, the great German
chemist Justice von Liebig conducted a series of
experiments and published a paper that established the "law of the
Minimum." That ecological axiom
states that "growth of a plant depends on the amount of foodstuff which is
presented to it in limiting quantity."
Even more simply, plant growth is always limited by a particular
environmental factor. Add more of that
factor and plants will grow until some other factor becomes limiting. The NRC scientists. recognizing that iron appears to be the factor limiting the
growth of phytoplankton, want to add more iron to the phytoplankton's habitat.
So
confident are the scientists of their solution that one of the leading
proponents of this remedy, John Martin of Moss Landing Marine Laboratories in
Needless
to say, no one on the NRC panel wants quite that much iron. Also, needless to say, no purposeful human
manipulation of the natural environment of this magnitude has ever before been
undertaken. And because the phytoplanklon are at the bottom of the ocean's food chain,
fed on by tiny zooplankton that, in turn. are eaten by
the fish and mammals of the sea, the ecological consequences of the addition of
iron might be enormous. This uncertainty alone might be reason enough not to
pursue such a massive manipulation.
But,
in fact, there is a far better reason not to proceed along the lines of the NRC
panel's recommendations, and that reason comes from medicine rather than
ecology. Doctors have long recognized
that it is far less productive to treat the symptoms of a disease rather than
the underlying causes. While aspirin,
for example, might be wonderful at bringing down a fever caused by a bacterial
infection, it will not help remove the offending bacteria. With the fever reduced, the patient may seem
to be improving only
to suffer a massive and perhaps deadly relapse when the bacteria reach immense quantities.
Fertilizing
the oceans with iron is like feeding aspirin to a sick patient. Increased quantities of phytoplanklon
might well reduce the amount of carbon dioxide in the atmosphere, but they will
not get at the root of the greenhouse problem.
And given the politics, both national and international, of attempting
to rein in emissions of offending gases, any program that appears to make such
control less immediately pressing is sure to add ammunition to those who would
rather not take any action at all. As
with an untreated bacterial infection, continuing to use our atmosphere as a
repository of unwanted pollutants is a prescription for suicide.
Regardless
of how much increased phytoplankton growth can be coaxed out of our oceans, the
amount of carbon dioxide that will be absorbed will never be infinite.
Ultimately,
then, we will still need to control our profligate habits if we expect to live
in harmony on this planet. Fertilizing
the oceans, while delaying the problem, will increase its magnitude and,
ultimately, will make finding an acceptable solution even more difficult. By delaying, we are doing what we do so well:
Bequeathing to our children our own most difficult problems. We should have the moral strength to act in a
more responsible fashion
Michael
Zimmerman is professor of biology
Oil
from Algae 5
From
Audubon Magazine Jan 1990
One of the most controversial offspring of the
energy crisis of 1973 and 1979 is the subsidized production of alcohol from
corn, for auto fuel. Burning alcohol
rather than gasoline reduces smog and our petroleum imports, but ethanol has
also acquired a reputation of being damaging to automobile engines and a
heavily subsidized alternative to straight gasoline.
Norm Hinman, a
biochemical engineer specializing in ethanol at SERI says the first problem was
solved several years ago:"Every auto
manufacturer will warrant its engines on a ten percent ethanol
blend". He agrees that the current
corn-fed approach, producing 850 million gallons of ethanol yearly is not going
to make much of a dent in the 112 billion gallons of gasoline that the nation's
engines burn every year (1990). But he predicts that ethanol production will
soon be increased to five billion gallons per year (Another type of alcohol
already is well established in one small but influential population of engines:
cars in the
The corn to alcohol process is simple as can be,
requiring only the fermentation of the sugars already in the kernels, along
with sugars produced from the starches.
SERI is heading down a different road using lignocellulose,
or plant fiber, as a feed stock rather than corn kernels. The difficulty is that lignocellulose
does not ferment until it is broken down into certain sugars and this is
difficult to do economically. Current
Biotechnology can break three quarters of the fibers into sugars, using acids,
enzymes, and yeast strains. (The
leftover lignin is useful in industry).
A full-scale plant, Hinman says, would look
like a cross between a corn wet milling factory and an
oil refinery.
Hinman says lignocellulose is worth using because it is inexpensive and
available in vast quantities, as a residue from current food and fiber
harvests. Take corncobs, which are
tossed out of corn harvesters onto fields every fall. All those cobs, Hinman
points out, could produce five billion gallons of ethanol a year.
At a gathering cost of $20 to $50 per dry ton, Hinman figures that lignocellulose
processing could produce the equivalent of 130 billion gallons of gasoline a
year, more than the current consumption (1990).
"That would produce a lot of jobs in the
As the technology stands now (1990), Hindman says, the production would cost $1.35 a
gallon. He admits that this figure is
far from the wholesale price of gasoline, about 50 cents (1990-oh how it's
changed!), but the progress has been rapid: in 1984 the cost was three times
higher. He is aiming for an
unsubsidized, wholesale cost of sixty cents a gallon or ethanol, which would
match the per-BTU cost of gasoline.
"I think its doable" he says "I
look at the progress we've made and think we can do it within ten years.
If you listened to biologist Lewis Brown long
enough, you might conclude that we should cover one percent of
The algae he has been experimenting with, as
manager at SERI’s biotechnology branch, is first
cousin to that in the ocean’s upper layers.
This algae, he says, absorbs about 1/3 of all the carbon absorbed by
plants worldwide. The ideal alga is
selected for its single-minded production of oil. With the water removed more than ½ of the
algae by weight is oil.
Brown has in mind building thousands of racetrack
shaped ponds just six inches deep. Algae
could flourish in the intense southwestern sunlight, and Brown estimates that
each acre could produce 150-400 barrels of refined fuel. In effect, these ponds would mimic the
ancient shallow seas that produced so much petroleum. Here however, tubes would bubble large
amounts of carbon dioxide through the water to boost algae growth. (What would
this do to the pH of the water???)
“Carbon dioxide is not the enemy.” Brown says, “without it plants won’t grow and we’d all die.” When questioned about proposals to discard
vast quantities of carbon dioxide underground or at sea, he responds, “Why not
give it to us and we’ll make use of it”?
He explains that algae in ponds is forty times
more efficient at taking up carbon dioxide than algae in the open ocean. A quarter of a percent of
Brown concedes that the recycled carbon would
enter the atmosphere eventually, as the algae-grown liquid fuel was burned in
cars, but points out that this approach would extend the carbon’s usefulness
before the harm started. How about water
lost to evaporation from the ponds?
“These farms could operate on existing brackish water supplies for many
decades,” he says. And the water that
becomes too salty from evaporation could go back underground.
Experimental ponds are operating near
The algae and lignocellulose
proposals came under the heading of biomass.
Power production from biomass, using energy stored during photosynthesis,
is well advanced in some industries. The
utility company in
1 Symptoms Treating a Symptom...
1. What would the
addition of iron to the ocean do?
2. How would this
work?
3. Why fertilize
phytoplankton?
4. Would this
cure the greenhouse effect?
5. After reading
this article, should scientists follow through with this idea?
2 Oil From Algae Energy...
1. List some
positive and negative effects of using ethanol in cars.
2. Where does Lignocellulose come from?
3. How much gas
per year could be produced from lignocellulose and at
what price?
4. How much of
our energy could be produced from algae?
5. How much of
the algae is oil?
6. What else
would be used to feed the algae?
7. How much would
a gallon of fuel cost?
8. Explain how would this recycle carbon
3 Wind Farms
1. What are some of the negative impacts wind farms can
have?
2. How tall are the towers?
3. How many megawatts of energy are produced per
year---what % is that of the
4. Besides power, what are some benefits of wind power
production?
5. What is happening to bats?