Friday, July 27, 2012

How is the Wind?

The sun is primarily responsible for life to exist, is also the ultimate energy source, since it is responsible for almost all renewable energies. In the case of wind energy is not an exception, because the sun is the wind that moves the wind element is producing sustainable energy.

Consider the formation of the wind: the crust absorbs solar radiation, but due to several factors, the absorption of solar energy is not equal at all points on the planet.  

Affect the energy absorption factors such as topography, differences in absorption capacity between marine and continental surface, the albedo (the ratio of reflected solar energy) cloudiness, or the fact that at some points while it is day others it is dark.

These differences between different parts of the cortex, causing the formation of large air masses are at different temperatures, resulting pressure differences in the atmosphere.

The air, like the rest of fluid tends to move from the places of higher pressure to areas of lower pressure, which causes air to move, ie, wind occur.

Looking at the weather map, we know the wind direction, as it goes anticyclones (high pressure zone marked with an A) to the storms (low pressure area designated as B). The anticyclones are associated with fair weather while weather storms.

Isobars are the lines that we see on the map, and connecting the various points that are at the same pressure. If there are many isobars together, this means that the pressure differences are more pronounced, implying that the wind intensity is higher.

It is estimated that a small part of the energy of sunlight is changing effective wind around a 1 or 2%. If we could harness all the wind, we could produce 53 TWh / year, wind power, which would cover the energy needs of the entire planet.

The current wind turbines do not allow all the wind advantage, but only energy-producing winds near the ground and parallel to the horizon, as long as its speed is greater than 3metros/segundo and less than 25 meters / second.

Wind turbines have evolved and become more effective, as the first to be built had a yield of 10%, while those currently seen in 50% advantage in energy.

Below you can see a couple of very interesting videos. In the first, a college student will demonstrate how wind is produced by a simple experiment.