The Earth is unevenly heated by the sun, such that the poles receive less energy from the sun than the equator; along with this, dry land heats up (and cools down) more quickly than the seas do. The differential heating drives a global atmospheric convection system reaching from the Earth's surface to the stratosphere which acts as a virtual ceiling. Most of the energy stored in these wind movements can be found at high altitudes where continuous wind speeds of over 160 km/h (99 mph) occur. Eventually, the wind energy is converted through friction into diffuse heat throughout the Earth's surface and the atmosphere.continue..

Wind power is produced by using wind generators to harness the kinetic energy of wind. It is gaining worldwide popularity as a large scale energy source, although it still only provides less than one percent of global energy consumption. The articles listed below explore wind power and its usage around the world.continue..

Wind power is actually a form of solar power, because wind is caused by heat from the sun. Solar radiation heats every part of the Earth’s surface, but not evenly or at the same speed. Different surfaces—sand, water, stone and various types of soil—absorb, retain, reflect and release heat at different rates, and the Earth generally gets warmer during daylight hours and cooler at night.
As a result, the air above the Earth’s surface also warms and cools at different rates. Hot air rises, reducing the atmospheric pressure near the Earth’s surface, which draws in cooler air to replace it. That movement of air is what we call wind..continue..

The historical and technical information in this section is derived from many sources. Information on developments since 1975 is based primarily on my personal experience with the U.S. Federal Wind Energy Program, my extensive reading (and editing) of wind energy journals and research reports over the last 25 years, my conversations with wind energy researchers, interactions with members of the wind energy community, and my personal view of wind power developments and of the wind industry. Opinions expressed here are my own, of course. --DMD.continue..

There are a range of advantages and disadvantages of wind energy to look at, including the many problems associated with wind turbines. In this day and age, the world needs to look at the different natural energy sources available to us. Global warming could be due our energy craving lifestyle, so we should look into more environmentally friendly energy sources.
1. Wind energy is friendly to the surrounding environment, as no fossil fuels are burnt to generate electricity from wind energy.
2. Wind turbines take up less space than the average power station. Windmills only have to occupy a few square meters for the base, this allows the land around the turbine to be used for many purposes, for example agriculture..continue..

Wind is a form of solar energy. Winds are caused by the uneven heating of the atmosphere by the sun, the irregularities of the earth's surface, and rotation of the earth. Wind flow patterns are modified by the earth's terrain, bodies of water, and vegetative cover. This wind flow, or motion energy, when "harvested" by modern wind turbines, can be used to generate electricity.continue..

The very nature of wind-powered generators makes them ideal to use in conjuction with other sources of energy. Wind and solar generators have been extremely successful as supplements to one another. The presence of the wind generator means that the other energy source does not have to be producing as much of the time.
Grid Connected
Grid Connected systems are already in wide use in areas that are already hooked up to a utility grid. Their main use is as a supplement to other forms of energy. This is important because average wind turbines only generate electricity about 25% of the time..continue..

Wind turbine technology is discussed in detail in Part 1. Turbine technology is also covered briefly in this section, to provide some background to the information that follows.
The traditional Danish stall-regulated wind turbine concept uses an induction generator.  Its rotational speed is fixed by the frequency of the electricity network to which it is connected. The blades are fixed - inother words they do not pitch - so the output power and structural loads in high winds are limited by passive stall regulation. Unfortunately this concept, though cheap, simple and reliable, has several negative effects on the electricity network:.continue..

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