Wind is the movement or flow of gaseous elements around earth surface. One of the most important characteristics of wind is its velocity. Another characteristic of wind is energy. It is affected by high and low pressure of air of that particular location or area. Earth surface is heated randomly by the sun which depends on the occurrence of sun ray's angle and surrounding of the land. Sun ray's angle can be varied with latitude and time of day. Water of the oceans heat up and cool down slowly in comparison to land. Heat energy which is absorbed in earth's surface is transferred to air directly above these oceans and lands. The density of warmer air is less in comparison to cooler air. These factors are creating constantly changing characteristics of wind across earth's surface. Economically generating wind power from wind is the total amount of economically extractable power available from the wind is significantly higher than power generated from all other sources. Wind energy is a renewable energy which is environment friendly.
What is a Wind Farm?
A Wind Farm or Wind Park is the assembly of wind turbines which helps to generate power from wind in the same area. Typically, a large wind farm has some individual wind turbines which covers prolonged areas. But, the land between the turbines should be utilized for agricultural or other purposes. It may also be constructed in offshore area.
Design of a Wind Farm
There should be a constant flow of non-choppy wind throughout the year having less possibility of stormy wind in the location of a wind farm. Basically, economic wind generators need wind speed of approximately 16 km/h (10 mph) or greater. An important factor of turbine siting is also access to local demand or transmission capacity.
Basically, a wind farm is planned and designed on the basis of a meteorological wind data charts as well as practically measuring actual wind speed of the area. In order to finance the project, it is very important to survey the area and collect the data of wind speed of that particular area. Sometimes, wind in local areas observed for a year or more. Before installing wind generators and detailed wind maps should be prepared.
Each turbine is connected to medium voltage through a combined power system and communications network. In order to increase the voltage of the power system, a step up transformer is used in a substation. Installation of collector system and substation are required to build up a land-based wind farm. A road access for each turbine is also required in the farm area.