An Overview of Wind Farms
Wind farms are typically composed of a collection of wind-turbines which are located near to each other. Wind farms come in a variety of sizes and structures. Farms can have more than hundreds of wind turbines working in unison to generate electricity.
Wind farms of today employ advanced technologies to optimize energy generation. Some of the largest wind farms in the world generate more than 6000 MW as of today with targets of reaching 20,000 by 2020. Wind farms are also often located on off-shore locations due to geographical and meteorological advantages.
Geographical requirements and wind turbine design
The bare-minimum wind-speed requirements for the operation of wind-turbines requires a speed of 16 kmph or higher. The nature of the wind needs to be non-turbulent. Ideal locations for wind farms demand an almost continuous supply of wind throughout the course of the year. There should also be zero to limited major fluctuations in the wind speed. Additionally, the location that has been chosen must have decent connectivity to the main grid for easy transmission.
Relying solely on meteorological data can prove to be insufficient especially for large wind farm projects. For successful establishment of wind-farms, site-specific long-term data on climate and variations in wind speed are required for assessment. Some of the factors that determine the wind-speed in an area are mentioned below.
- As the altitude increases, the wind speed also increases due to lesser drag effects.
- Topography and roughness of the surface also play an important role in determining the wind speed and turbulence in the area.
- Presence of upwind hurdles such as large vegetation coverage or the presence of tall buildings can significantly affect wind-speeds in the area.
One of the main factors that determine the efficiency of wind farms is the separation between each individual wind turbine. If the turbines are placed too close to each other, then the turbines for the upwind block a significant portion of the winds from reaching the nearby turbines. If the turbines are placed too far from each other, then it entails significant investments in transmissions and infrastructures. Additionally, roads and other resources often get disrupted due to wind farms being placed too far away from each other.
Challenges in adoption of Wind energy
Most studies indicate that the major hurdle against wind energy is the opposition from people. While wind energy, much like other renewable sources of energy does have significant environmental benefits, the limitations on geographical locations and the weather conditions pose serious challenges in its applications.
Quite often the locations which are perfect for the application of wind energy are so remotely located that connection to the grid seems impossible. Added to this, residents who live near wind farms complain about the “flicker-effect” that is often created when wind turbines are located directly in front of the sun. There is no substantial evidence to support “wind-farm syndrome” which is said to be caused by the continuous sounds of the wind-turbines and the ecological impacts of local wildlife such as birds getting affected by turbine operations are fairly minimal.