Energy Tic-Tac-Toe BoardRenewable Source -

Wind Energy

By: TJ Hoyt

What Makes Wind

The sun shines on land and water.

Land heats up faster than water.

Warm air over the land rises.

Cool air over the water moves in.

Wind in Action

When wind strikes an object, it exerts a force in an attempt to move it out of the way.

Some of the winds’ energy is transferred to the object, in this case the windmill, causing it to move.

History of Wind Energy

5000 BCSailboats used

on the Nile indicate the

power of wind

500-900 ADFirst

windmills developed in

Persia

1300 ADFirst

horizontal-axiswindmills in

Europe

1850sDaniel Halladay andJohn Burnham build Halladay Windmill;

start US Wind Engine Company

Late 1880sThomas O. Perryconducted 5,000

wind experiments;starts Aermotor

Company

1888Charles F. Brush used windmill to

generate electricityin Cleveland, OH

Early 1900sWindmills in CA

pumped saltwaterto evaporate ponds

1941In VT, Grandpa’s

Knob turbinesupplies power to town during WWII

1979First wind turbinerated over 1 MWbegan operating

1985CA wind capacity

exceeded 1,000 MW

1993US WindPower developed first commercial variable-

speed wind turbine

2004Electricity from wind generation costs 3 to 4.5 cents per kWh

2011Wind power provided

over 12% of renewable

energy used in US

Why Wind Energy?

Clean, zero emissions

NOx, SO2, CO, CO2

Air quality, water quality

Climate change

Reduce fossil fuel dependence

Energy independence

Domestic energy – national security

Renewable

No fuel price volatility

Wind Energy Natural Characteristics

Air density Wind energy increases proportionally with air density

Humid climates have greater air density than dry climates

Lower elevations have greater air density than higher elevations

Blade swept area

Wind energy increases proportionally with swept area of the blades

Blades are shaped like airplane wings

10% increase in swept diameter translates into 21% greater swept area

Longest blades up to 413 feet in diameter

Resulting in 600 foot total height

How to Convert Wind into Electricity

Wind turbines convert the kinetic energy in the wind into mechanical power. This mechanical power can be used for specific tasks (such as grinding grain or pumping water) or a generator can convert this mechanical power into electricity.

A wind turbine works the opposite of a fan. Instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity. The winds turns the blades, which spin a shaft, which connects to a generator and makes electricity.

The energy in the wind turns two or three propeller-like blades around a rotor. The rotor is connected to the main shaft, which spins a generator to create electricity.

Wind turbines are mounted on a tower to capture the most energy. At 100 feet or more above ground, they can take advantage of faster and less turbulent wind.

Advantages of Wind Energy

Wind energy is free.

Wind is a completely renewable resource because it is something that occurs naturally.

There is no pollution.

Wind energy is friendly to the surrounding environment, as no fossil fuels are burnt to generate electricity from wind energy.

Wind turbines requires less space than average power stations.

They are the lowest prices renewable resources.

They do not produce atmospheric emissions that cause acid rains and green house effects.

No water needed for operations.

Disadvantages of Wind Energy

The winds unreliability factor. In many areas, the winds strength is not enough to support a wind turbine.

Noise and aesthetics.

Wind turbines generally produce a lot less electricity than the average fossil fuelled power station, which means that multiple wind turbines are needed to make an impact.

Depending on how energetic a wind site is, the wind farm may or may not be cost competitive.

Wind energy cannot be stored (unless batteries are used).

Good wind sites are often located in remote locations.

Wind resource development may compete with other uses for the land and those alternative uses may be more highly valued than electricity generation.

Sometimes birds and bats have been killed by flying into the rotors.

And Now

Modern wind power is a strong option for alternative energy and its rich history proves it can be used effectively.

Wind energy is very abundant in many parts of the United States.

Wind energy production was around 4% of total worldwide electricity usage and is growing rapidly.