Energy From the Wind

Wind Energy

Let the wind turn the crank to produce electricy.

Windfarms are now popping up and selling electricity to the grid at around 4 cents per KWH and costs are projected to lower. Modern turbines, such as those pictured below, can achieve efficiencies of up to 40%.

Windfarms containing up to 5,000 individual wind turbines have now been created such as this facility in California (near Stockton).

Of course, the idea of a windmill as a device to turn a wheel has been around for centuries

which proliferated in Holland (a flat, windy place where Don Quixote hung out).

In the 1920's and 1930's the rotary style windmill, shown belown, became a common mixture on farms in the Midwest as a means of running a water pump

Recently, aviation technology has advanced windmill design quite a bit to produce todays's modern wind turbines:

The concept of the windfarm is now being put into practice:


Main problem with wind is its erratic nature.

Power per square meter goes as (wind velocity)3 requires good energy storage for later use.

What makes the wind blow?

While wind is certainly a renewable energy source, it is also an erratic one. Energy storage is probably more critical for wind power than for any other form of alternative energy.

Basics of Wind Energy:

For average atmospheric conditions of density and moisture contant:

(Don't memorize .0006 V3; you will never need to know the 0.0006 part!)

Example Problem:

Example calculation:

To Generate 10,000 KWH annual then from a 20 mph wind that blows 10% of the time

Wind Energy can be competitively priced:

Current Grid Connected Wind Power:

    Country/region          MW Installed
        ------------------------------------
        United States   -       1700
        Denmark         -       520
        Germany         -       330
        United Kingdom  -       145
        Netherlands     -       132
        Spain           -       55
        Greece          -       35
        Italy           -       10
        Other OECD      -       70
        India           -       50
        China           -       25

Some aggressive goals for wind power:

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