Because there have been some chats/discussions about the environmental impact of wind energy. I did some quick research on that topic, that shows very clearly, that wind-power is one of the most sustainable ways of producting energy. A wind-mill-constuctions energy “pay back” seems to be only around 8 months. (compare: PV-powerstations with 2-5 years energy “pay back” time)
Here is the chapter form the Wikipedia-Article:
Carbon dioxide emissions and pollution
Wind power consumes no fuel and no water for continuing operation, and has no emissions directly related to electricity production. Wind turbines produce no carbon dioxide, carbon monoxide, sulfur dioxide, nitrogen dioxide, mercury, radioactive waste, particulates, or any other type of air pollution, unlike fossil fuel sources and nuclear power plant fuel production. Wind power plants consume resources during their manufacturing and construction, as does every other type of powerplant. During manufacture of the wind turbine, steel, concrete, aluminium and other materials will have to be made and transported using energy-intensive processes, generally using fossil energy sources. Wind turbine manufacturer Vestas claims that initial energy “pay back” is within about 8.6 months of operation for a V80-2.0MW wind power plant under low wind conditions.
- CO2 emissions
A 2006 study found the CO2 emissions of wind power to range from 14 to 33 tonnes (15 to 36 short tons) per GWh of energy produced. Most of the CO2 emission comes from producing the concrete for wind-turbine foundations.
A study by the Irish national grid stated that “Producing electricity from wind reduces the consumption of fossil fuels and therefore leads to emissions savings”, and found reductions in CO2 emissions ranging from 0.33 to 0.59 tonnes (0.36 to 0.65 short tons) of CO2 per MWh.
- Rare-earth mining pollution
The production of permanent magnets used in some wind turbines makes use of neodymium. Primarily exported by China, pollution concerns associated with the extraction of this rare-earth element have prompted government action in recent years, and international research attempts to refine the extraction process. Research is underway on turbine and generator designs which reduce the need for neodymium, or eliminate the use of rare-earth metals altogether. Additionally, the large wind turbine manufacturer Enercon GmbH chose very early not to use permanent magnets for its direct drive turbines, in order to avoid responsibility in the bad environmental imprint of rare earth mining.