There are many different types of energy in this beautiful world of ours. One of those is wind energy. Wind energy is mainly used to generate electricity, and it [wind] is a renewable energy source. Wind energy is really just energy from the wind. Wind is created when warm air over land expands and rises, while the heavy, cool air rushed to take it's place. (This is what happens during daytime. At night time it is the opposite.) This will always happen, so we will always have wind.
We can generate this wind energy using wind turbines. Wind turbines use blades to collect the wind's kinetic energy. The wind flows over the blades, which creates a lift (like airplane wings), and it causes it to turn. The blades are connect to a drive shaft which will turn an electric generator and produce electricity.
Wind energy is used all around the world, although many countries don't use wind turbines to get the energy. In the US, about 1.3% of total electricity generation came from wind energy (in 2008). Here in the US, electricity generated by the wind has increased in the past few years. So it's not that common yet, but soon it will be. Especially since the cost is decreasing due to new technology, and because of tax breaks and green pricing programs.
Drawbacks/limitations:
1)It is very hard to find a good site to place wind power plants due to location (preferably rounded hills, open plains, shorelines, and mountain gaps) and because wind speed changes by season. (But on the bright side, the seasonal variations are a good match for electricity demands of the regions.)
2) They are large and make a loud noise, which people do not like. Also, with it being so large, many birds and bats are killed by the blades.
3) Making the metals and other materials for wind turbines and concrete for their foundations require energy, mainly through burning fossil fuels. (But, studies show that the amount of clean energy created is greater than the amount it takes to make and install them.)
Positive Aspects:
1) It is a renewable source of energy, so it will never have a limit.
2) They, the wind turbines, create a clean source of energy. Along with this, it has fewer environmental impacts than other energy sources. They also do not release emissions that pollute the air or water and do not require water to cool down.
3) They may reduce the amount of electricity generated from fossil fuels, therefore reducing the amount of air pollution, CO2 emissions, and water use of fossil fuel power plants.
4) Many wind projects, or wind farms, are located on farm, grazing, and forest land. The extra income allow farmers and ranchers to stay in business and keep their property from being developed for other uses.
Pictures:
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Source: http://www.eia.doe.gov/kids/energy.cfm?page=wind_home-basics (Great site with lots of information, although I already mentioned most of it. *hint, hint* This contains some information we learned in class and that we might have to know. *hint, hint*)
~Jess