| Wind power, or wind energy, is a renewable | | | | Often wind turbines are grouped together; the |
| resource; it is from the sun. The advantages of wind | | | | arrangement in called a wind farm that provides |
| power are many, including practical, environmental as | | | | energy to an electrical grid. |
| well as economic. There are also disadvantages to | | | | Vertical axis turbines are more efficient in areas with |
| using windpower, such as the natural variability of | | | | vast amount of lands and moderate wind speeds. |
| wind, the competition for other land uses, and bird | | | | Current technology is looking to develop different |
| deaths. | | | | turbine types for different areas of wind speed given |
| Wind power, or wind energy, is a renewable | | | | the amount of land available for farms. |
| resource; it is from the sun. The intensity of solar | | | | The advantages of wind power are many, including |
| radiation differs across the globe. Some areas receive | | | | practical, environmental as well as economic. |
| intense amounts of sunlight, while others receive | | | | Worldwide, the total kinetic energy contained in wind |
| much less. The result is a temperature gradient; a | | | | is more than 80 times that of human energy |
| gradient which is mediated by the flow of air to and | | | | consumption. While only a fraction of this can be |
| from areas of dissimilar temperatures and pressure | | | | used for electricity purposes, the potential-given |
| systems in our atmosphere. Uneven heating of the | | | | future technological developments is great. |
| earth's atmosphere,in addition to irregularities on the | | | | Environmental advantages include the fact that a |
| earth's surface and the rotation of the earth create | | | | renewable source of clean, nonpolluting energy curbs |
| wind. Terrain, water bodies, and vegetation then | | | | the demand and use of fossil fuels and emit no air |
| shape flow patterns. | | | | pollution of greenhouse gases, In the US, wind plants |
| The recent history of wind power in the United | | | | have offset the emission of than 2.5 billion pounds of |
| States has a similar impetus to that of alternative | | | | carbon dioxide, and 15 million pounds of other |
| fuel sources in general - it was an idea borne from | | | | pollutants. Also, wind energy is free: the cost of |
| the 1970's Oil Crisis. It does, however, have a more | | | | installation and maintenance has dramatically |
| extensive history reaching back into to late 19th | | | | decreased in recent years and future technology |
| century in the colonization of the American West; | | | | ensures only a continual decrease in the prices. As a |
| millions of windmills were erected for irrigation and | | | | result, the lifetime investment is much lower than |
| cattle purposes to facilitate the growing number of | | | | most fossil-fuel systems. |
| farms and ranches. Many soon feel into disrepair as | | | | One of the primary disadvantages to wind power is |
| inexpensive energy sources became more | | | | the natural variability of wind in any given locale. |
| widespread and grid power extended its reach into | | | | Indeed there are certain areas with extremely high |
| rural areas used small electric wind systems. | | | | average wind speeds, but in most places, wind |
| Outside of the US, however, wind power has a | | | | exposure is quite variable. Wind energy can only be |
| broader history. In fact, there was evidence that | | | | stored with a battery, otherwise it is not. In the |
| boats were propelled along the Nile as early as | | | | latter case, not all energy demands can be met |
| 5000BC via wind energy. China used wind for | | | | through the natural timing of winds. For these |
| pumping water several millennium ago. | | | | reasons, it may not be a viable option for some. One |
| Wind is harnessed to make mechanical power or | | | | other disadvantage is the competition for other - |
| electricity. The kinetic energy from the wind is | | | | more highly valued and profit generating - land uses. |
| converted through various different processes to | | | | Economic disadvantages include the fact that the |
| create mechanical energy that can be used in lieu of | | | | initial investment is often higher than fossil fuel |
| fossil fuels. There are two types of modern turbines | | | | systems. The higher costs is mostly due to the |
| - horizontal and vertical axis, both of which work | | | | machinery which is involves. Other costs include site |
| similar to one another and as decried above. Between | | | | preparation and installation. The primary environmental |
| the two types, they come in an array of sizes from | | | | drawbacks to wind power are as follows: Noise |
| small 100 watt units for single homes to much larger | | | | pollution via the rotor blades Aesthetic impacts |
| or ones (with a blade diameter greater than 50m). | | | | ("visual pollution"), and bird deaths. |
| These larger turbines can generate 1 MW of | | | | It is important to keep in mind that many of these |
| electricity. | | | | problems have been resolved with increasing |
| The most common used today are horizontal axis | | | | technology. Avian mortality, however, is still being |
| turbines with three blades (15-30m in diameter) and | | | | studied. |
| produce approximately 50-350 kW of electricity. | | | | |