Wind energy, as a renewable energy source is getting more and more scientific and industrial attention. Most of the countries are now mainly relies on petroleum based fuels for energy. To build a energy secure country we have to change our main energy source from oil to renewable energy sources. Increasing prices of the oil affects the economic growth of a country.
There are several renewable or alternative energy sources some of which are only available in special areas. Wind energy, hydroelectric power,tidal power,wave energy,geothermal energy,
solar power are some examples of renewable energy sources.
Utilising wind energy by using wind turbine is an easy task. A major advantage of wind energy relative to nuclear, geothermal,fossil and solar central receiver systems is that wind based generation of electricity does not need cooling water.
Even though there are environmental impacts that are caused by utilizing wind energy. Even a single wind turbine requires to clean decks a large area for turbine, roads, transmission lines and other infrastructures. If the site planned to build the turbine is located inside a forest with adequate availability of wind for power generation, it requires to remove everything including several ecosystems and trees.
|Klipheuwel wind-farm by warrenski, on Flickr|
Environmental impacts of Wind power
1. Causes stress to the ecosystem
Do you know how wind produces in the atmosphere? Uneven heating of earth surface and atmosphere causes flow of air which is termed as wind. Can you imagine what will happen if there is no wind? Large scale generation of electricity through windmills can reduce wind-speeds and cause stress to the ecosystems. Nature plans something but we destroys them. We have no permission to alter anything that nature decided. To maintain an atmospheric balance flow of air between low temperature side and high temperature side is essential. Building wind farms across this air flow may affect the ecological balance.
2. Disturbance to bird life
Usually large wind mills or turbines are fitted on a tower located several meters from the ground. The rotation of the turbine blades make some disturbance to flying birds. How much you will feel angry if someone blocked your way without any reason? Aren't we disturbing their freedom? If the turbine is located in the migration route of birds there is a higher possibility for the extinction of a species of birds.
3. Causes noise pollution
There are two principal sources of noise in the wind turbine. A. The machinery in the nacelle,which can be avoided by good and efficient design and acoustic insulation B. Swinging sound from the rotating blades. We cannot avoid this kind of noise. The noise generated by a wind machine increases with the wind speed. Some of the noise produced by the turbine blades are below audible range usually in infra sound frequency. Vibrational disturbance caused by these infra sound may cause houses and other structures to vibrate. Why these infra sound is produced? The infra sound is generated by the turbulence that is set up by the rotating blades and interacts with the tower structure.
4. Aesthetic degradation
If a large wind farm is built in a natural landscape, which will reduce the natural quality that people interpret as making it less attractive.
5. Badly affects wild life
During a recent survey of the area adjacent to Blyth Harbour wind farm, which has a large population of birds including rare purple sandpipers, about 1000 animals were found dead. If the wind turbines are located in migration routes which may pose a hazard to birds and bats. Wind farms badly affects the habitats.
6. Television interference
Broad signals produced by the wind turbines can cause television interference, electromagnetic interference,or microwave interference. The problem is caused by the Rotor blades which intercept the television beam, and by the tower structure which scatters the beam.
7. Reduces rate of evaporation
Lakes that are downwind from the windmills might become warmer because of reduced evaporation from their surface. Which will affect fresh water organisms lives in lakes. Besides wind mills causes soil moisturization which may badly affect the crops.
We want energy. We don't have any sentiments on other living organisms. Building a large wind power station in a forest area having high wind energy potential requires deforestation. About 4-6 acres of forest is clear cut for each turbine. Deforestation causes destruction of several habitats and natural ecosystem.
9. Shadow flicker
When the sun is behind a wind mill, it creates a shadow that appears to flicker in and out with the rotation of the blades, which causes problems in around 5 percent of people with epilepsy.