Transcript Overall Criticisms of Wind Turbines

Overall Criticisms of Wind Turbines
• wind power is an intermittent power source. The production from a
wind turbine may increase or decrease dramatically over a short
period of time with little or no warning. In the absence of large
scale energy storage, the balance of the grid must be able to quickly
compensate for this change. A proposed solution is a super grid of
wind farms.
• Economics: high quality wind resources are often located in areas
inhospitable to people, logistics and transmission capacity can
introduce significant obstacles to new installations.
• The impact of wind turbines on wildlife has often been cited as a
disadvantage of wind installations. Wind turbines can pose a danger
to birds and bats, though the magnitude and gravity of this danger
may be much less than threats such as house cats or plate glass.
Wind Turbine Syndrome
A condition which may be related to prolonged exposure to the low
frequency sound waves (Infrasound) that come from wind turbines.
Symptoms of wind-turbine syndrome might include:
• headaches
• sleep problems
• night terrors or learning disabilities in children
• ringing in the ears (tinnitus)
• mood problems (irritability, anxiety)
• concentration and memory problems
• issues with equilibrium, dizziness and nausea
NO conclusive evidence that this is real. Note that all of these
symptoms are also produced by not sleeping well
Infrasound
• Sound at frequency lower than 20 hz.
• Humans do not hear this, but the ear senses
it. Known to cause feelings of awe and fear in
humans.
• No agreement among scientists as to the
extent and impact of such noise from wind
turbines.
• Modern turbines are being engineered with
dampening systems to reduce such noise.
Wind Farms
• A group of turbines in the
same location
• 3 types:
– Onshore- within 30km of
the shore line
– Near shore -within 3km of
the shoreline or 10 km
offshore
– Off shore -more than 10Km
from land
• Noise is a big issue for
onshore and near shore,
as is aesthetics
Offshore wind farms
Offshore wind farms
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less obtrusive than turbines on land
apparent size and noise is mitigated by distance.
the average wind speed is usually considerably higher over open water.
Offshore installation is more expensive than onshore
Offshore towers are generally taller than onshore towers once the submerged
height is included.
Offshore foundations may be more expensive to build.
Power transmission from offshore turbines is through undersea cable
Offshore saltwater environments also raise maintenance costs by corroding the
towers, but fresh-water locations such as the Great Lakes do not.
Turbine components (rotor blades, tower sections) can be transported by barge,
making large parts easier to transport offshore than on land, where turn
clearances and underpass clearances of available roads limit the size of turbine
components that can be moved by truck. Similarly, large construction cranes are
difficult to move to remote wind farms on land, but crane vessels easily move over
water.
Offshore wind farms tend to be quite large, often involving over 100 turbines.
Cape Wind Project
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Approved offshore wind farm off of Cape Cod, MA.
130 wind turbines would produce a maximum of 454 MW enough
power for 420,000 homes.
Would provide 75% of the electrical needs to Cape Cod.
and the Islands
Concerns included ruining the views from people's private property.
Views from public property such as beaches (even though it would be about twenty or so
miles offshore, people complained it would ruin their views of the horizon).
decrease property values.
ruining popular areas for yachting.
the proposed wind farm would be located near shipping lanes.
Local fishermen, cite the fact that for many of them, up to 60% of their annual income comes
from catch caught on Horseshoe Shoals, which they claim would disappear and would have
to be replaced by steaming to fishing grounds farther out to sea if the project is completed.
Some who oppose the project are concerned about the corporate privatization of public
property.
Geological testing of the offshore site has begun.
Interesting co-generation idea with cars
and wind turbines
• Turbines suspended
over highways.
• Each turbine can light a
medium size apartment
TVA wind farm near Oak Ridge
Ocean Thermal Energy
• Energy is available from the ocean by
– Tapping ocean currents
– Using the ocean as a heat engine
– Tidal energy
– Wave energy
Energy from ocean currents
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Ocean currents flow at a steady velocity
Place turbines in these currents (like the gulf
stream) that operate just like wind turbines
Water is more than 800 times denser than
air, so for the same surface area, water
moving 12 miles per hour exerts about the
same amount of force as a constant 110 mph
wind.
Expensive proposition
Upkeep could be expensive and complicated
Environmental concerns
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species protection (including fish and marine
mammals) from injury from turning turbine
blades.
Consideration of shipping routes and present
recreational uses of location
Other considerations include risks from
slowing the current flow by extracting energy.
VIVACE-Alternate to turbines
The ocean as a heat engine
• There can be a 20° difference between ocean
surface temps and the temp at 1000m
• The surface acts as the heat source, the deeper
cold water acts as a heat sink.
• Temperature differences are very steady
• Florida, Puerto Rico, Hawaii and other pacific
islands are well suited to take advantage of this
idea.
• Called OTEC (Ocean Thermal Energy Conversion)