• Wind turbines along with PV cells provide some of the cleanest and cheapest power today. They are usually installed on farmland already cleared of trees. 
• They are compatible with most forms of farming and give the farmer a reliable source of income.
• It occupies less land per KW than any other energy generation technology apart from rooftop PV. They use 1-3% of their land area.
• It generates the energy used in its construction in three to seven months of operation, yet its operational lifetime is at least 20 years.
• There are no emissions or pollution produced by its operation, apart from noise over a limited range.
• In the USA typical bird death rates are two per turbine per year, and some European studies find about one-tenth of this.
• Large wind turbines convert into electricity about 45% of the wind passing through the area 
  swept out by the blades.
• Wind farms have a capacity factor of 20-40%. I.e, they generate that much of their capacity due to wind fluctuations.
• Wind power could contribute up to 20% of Aust. electricity by 2020 and substantially more by 2030.
• The more wind turbines installed across the country, the more steady is the supply of power
• Nowadays wind power generation can be predicted with increasing accuracy from hour to
  hour and from day to day

GE wind turbine

Vertical axis wind turbines

With a vertical axis wind turbine, the main motor shaft runs vertically instead of horizontally which means the generators and gearboxes are placed near the ground where it is more convenient for servicing.

One advantage of the vertical axis turbine is that the wind can come from any direction. They could be mounted with the axis horizontal by would need to pointed across the wind.

They operate at lower speeds than the normal propeller style so are quieter and can be used in residential areas.

They don't tend to be used at the height of the standard turbines so do not receive the faster winds

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McCamley turbine. A cage of fins direct the wind onto a centrl rotor. Video

Prof Diesendorf (UNSW) has produced a Submission to Senate Public Inquiry on the Social and economic Impact of Rural Wind Farms  This is an excellent list of the advantages of wind power and answers to various objections.

Wind spire