Wind Turbines

Wind power is actually a derivative form of solar power. The sunlight hitting the earth's atmosphere causes the air to heat, and the heated air rises as it becomes less dense. This gives rise to the upper atmospheric winds. They exist more than a mile above the surface of the earth, and they actually contain much more energy than the wind closer to the surface.

The sunlight gives away some of its energy to the atmosphere, but a good portion of it makes it to the surface, where it strikes either water or land. Water is less thermally responsive than land, and so the oceans can absorb a lot more sunlight than the continents can without warming to the same temperature. This causes a difference in air pressure over the oceans and the land. During the day, when the land is hotter, breezes flow out to see. After the sun sets the land cools off, the ocean retains more of its heat however, and it becomes warmer. Thus at night the breezes blow back in towards the land. Similar effects occur in range of mountains as well, with mountain and valley winds alternating during different times of the day.

The off-shore spots that are always in some form of wind make for a great spot to set up wind power. This is because on the ocean, there are no impediments to the wind's flow, and so the same force can build up more momentum without being interrupted. While off shore sites are the most promising in terms of yields, in general any place without landmarks to break up the wind's flow will produce a good yield of wind power. The major difference is that not all flat spots on land receive a large wind flow each year.

Wind power is clean power, just like solar power is. Neither of them creates pollution once the power generation system is in place, and neither of them requires an outside fuel source unless you count sunlight and breezes as fuel. They have a low environmental impact, even when compared to other forms of clean energy such as hydroelectric. And since wind still uses a turbine as a means of electrical generation, it can take advantage of more than a century's worth of innovations involving turbines.

Solar power is unique in that it alone among major methods of power generation does not utilize a turbine. A turbine operates on the simple principle that if you spin a magnet inside a coil of a conductive material such as copper, the coil will emit an electrical charge. Nuclear plants, coal fired plants, hydroelectric plants, geothermal plants, and even wind farms are all utilizing different energy sources to spin a magnet, but that is what they are all doing. Solar power is dissimilar because it utilizes a property called photovoltaic emission. Photovoltaic materials give off electrons when they are struck by sunlight. There are no moving parts involved, unlike a generator, however solar has struggled to reach the same efficiency levels that other methods, such as wind power, already enjoy.