Alysse Riggs and Julie Davis

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25 Νοε 2013 (πριν από 4 χρόνια και 7 μήνες)

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Riggs and Julie Davis

General Information

In reality, wind energy is a form of solar energy

The sun's radiation heats different parts of the
earth at different rates when different areas absorb
or reflect at different rates.

Hot air rises, reducing the atmospheric pressure at
the earth's surface, and cooler air is drawn in to
replace it.

Air has mass, and when it is in motion, it contains
the energy of that motion("kinetic energy")

The Main Goal

To create alternative energy
that was renewable

That did not create
pollution in the air and

That could replace
nonrenewable sources and
pollution in the near future

Making A Difference

It is a clean source of renewable
energy that does not create air or
water pollution

The biggest wind turbines can
power over 600 houses

Global capacity was
approximately 70,000 megawatts
(1 megawatt can power over 250

By 2050 the answer to one third
of the world's electricity needs
will be found blowing in the

The Wind Turbines

Two Groups of wind turbines:
axis turbine and
axis turbine (egg

Turbines are made of steel. The
blades are made of fiberglass
reinforced polyester or wood

The output of a wind turbine
depends on the turbine's size and
the wind's speed through the

Wind Turbines Cont.

A wind energy system transforms
the kinetic energy of the wind into
mechanical or electrical energy

Electricity production and
consumption are most commonly
measured in kilowatt
hours (kWh).

A kilowatt
hour means one kilowatt
(1,000 watts) of electricity produced
or consumed for one hour.

Ex: One 50
watt light bulb left on for
20 hours consumes one kilowatt
hour of electricity (50 watts x 20
hours = 1,000 watt
hours = 1

Technological Obstacles

Wind turbines

Below 8
10 mph wind speed they do not
generate and have to cut out for safety reasons above 56 mph.
Their maximum generation is reached at about 30 mph.

Wind Farms

generate some power for 70
75% of the time but
this is often a mere trickle, so the total electricity produced is
only about 26% of their full potential.

The electricity produced cannot be stored and feeding it into the
national grid is complex and costly

a bill ultimately paid by the

Coal or gas
fired power stations are essential to maintain
uninterrupted supplies of electricity when the wind is not

Developers claim a turbine lifespan is 20
25 years but many are
being replaced after just 9
12 years

with yet larger turbines

Political / Economic Obstacles

The electricity produced cannot be stored and feeding
it into the national grid is complex and costly , which
is ultimately paid by the consumer.

Wind turbines are being replaced every 9
12 years
which is costing more money

Negative Environmental Impacts

A turbine 375 feet high requires a
base of some 1000 tons of reinforced
concrete, to say nothing of the
materials needed to build service
roads. Together with peat
destruction on peat
rich sites, this
means that wind farms can take
years to pay back the carbon dioxide
they release during and after
construction, reducing even further
their contribution to climate

Birds unaware of wind turbines
often crash into them and are killed
as a result.