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Wind power is when we covert the power of the wind, physical energy, to more useful types of energy. The most common type of energy it is converted to is electricity. A wind farm is a large area of land on which there are a number of wind turbines generating electricity, as a power plant does. When creating a wind farm one must make sure that the spacing between the turbine is sufficient as not to cause energy/wind loss. The most common type of energy generated from wind is electrical energy. This is by making the use of an electrical generator which is turned by turbine blades which are turned by the wind and thereby turning the turbine, creating electricity.
©http://www.eia.doe.gov/kids Yes, as we find wind throughout the world and the minimum wind speed needed is from 16km/h upwards. The wind needs to have a constant speed, should be non-turbulent and must not be subject to strong bursts of air. The wind also blows faster the higher into the atmosphere you go. That is why most wind farms are found quite high up. You get three types of wind farms:
On Shore If a wind farm is about three kilometres away from the nearest shoreline it is regarded as an on shore wind farm. They are normally installed in the mountainous areas as the higher you go the faster the wind blows. The cliffs and mountains also contribute to speeding up the wind. Before setting up a wind farm much research has to be done because the smallest diffenrence of placement could even double the turbines' output.
©http://www.eia.doe.gov/kids Near Shore If a wind farm lies on land within three kilometres to the nearest shore line or lying on the water within ten kilometres from the shore it is considered a near shore wind farm. Sea shores tend to be very windy as the land and sea heat up and cool down at different rates, creating strong winds. The wind from the sea is also more dense and therefore carries more energy than the same speed wind in mountainous terrain. Off Shore If a wind farm is more than ten kilometres into the sea form a shore then it is considered to be off-shore. Off-shore turbines are found in deep sea waters and are usually much larger than their land-based siblings. The wind over the open sea is considerably faster and stronger than that of land because they have no obstacles in their way such as trees and buildings to affect the wind speed. Their distance from land allows companies to create larger ones and they do not need to worry about any noise factors as they are a considerable distance from the shore. The off-shore wind farms are the most expensive to build as they need to be set in the open ocean where they are subjected to all the earths's elements, therefore raising the maintence cost of off shore wind farms. The cost involved in transferring the electricity from the turbine to the land could be large as there is a large distance to be covered. Off shore wind farms are much larger than the on shore counterparts as there is much more space in the open sea as opposed to land and there are no worries of people complaining about them in the sea. Airborne This is a new concept with no product available as yet but there are companies busy developing an airborne wind turbine which is suspended high in the atmosphere thereby obtaining the fastest and strongest winds available.
Currently, South Africa does not have any wind farms which supply the national grid, but there are numerous projects to get them up and running. Two pilot projects which involve the use of wind farms to supply the national grid are located at Klipheuwel and Darling both of which lie in the Western Cape. The project at Darling is set to be up and running this year while the wind farm at Klipheuwel is in its first year of its three year experimental stage. The farm at Kilpheuwel which costs R42 million to set up consists of only three wind turbines with the biggest being 60 metres in height and having a blade length of 33 metres. South Africa is regarded as having the potential to become a worldwide wind powerhouse, and with Eskom, South Africa's largest electricity company spending millions on research and setting up wind farms, South Africa's wind power future is looking bright. The wind farm at Klipheuwel in the Western Cape is the biggest wind farm in sub-Saharan Africa. The cost of wind generators has dropped substantially since they were commercially brought into use in the 1990s. The price continues to drop as companies develop better and cheaper ways of creating the wind turbine. The greatest part of the cost involved in setting up wind turbines is the initial capital needed, the wind turbine has zero cost for fuel and the maintenance cost is low when compared to other forms of renewable sources of energy.
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