Wind
Wind Energy – how it works
Wind energy, currently the cheapest renewable energy source, involves the generation of electricity from the naturally occurring power of the wind.
Wind turbines capture wind energy within the area swept by 
their blades, proportional to the wind speed cubed, up to the designed maximum blade speed. The blades in turn drive an electrical generator to produce power for export to the grid.
Sites where there is strong, consistent wind, such as Southern Australia, are the most appropriate locations for wind farms. An excellent wind site is generally considered to provide average wind speeds greater than 8 metres per second at ground level.
Greenhouse gas savings
In 2009 estimated wind energy generation saved Australia 4,284,000 tonnes of carbon dioxide. That is equivalent to:
• the removal of 952,000 cars from our roads
As an additional environmental benefit, no water is needed for wind farm operation.
In Australia
Australia has some of the world’s best wind resources. The total operating wind capacity at the end of 2009 was 1712 megawatts - a 31 percent rise on 2008. This equated to a generation of approximately 4,284 gigawatt hours of electricity annually. So far in 2010 one new wind farm has been commissioned and the total operating capacity now stands at 1769 megawatts - generating around 5,000 gigawatt hours of electricity annually.
Currently there are 52 operating wind farms in Australia, with a total of 1,011 operating turbines. South Australia has the largest installed capacity around 45 per cent of the nation’s total capacity.
Potential
There are currently over 7,000 megawatts (MW) of large-scale wind farm energy projects proposed around the country, many of them having already received planning permission.
Global view
The use of wind power continues to grow around the world. Global installed capacity at the end of 2009 was almost 158 gigawatts - a 31 percent increase on 2008 - producing approximately 340 terrawatt hours of electricity annually.
In 2009, more than 37 gigawatts of new wind capacity was installed around the world with a value of around $US63 billion.
The top four wind energy nations are:
• United States - 35,159 MW
• Germany - 25,777 MW
• China - 25,104 MW
• Spain - 19,149 MW
Current Issues
In 2007 the Government committed to ensuring that 20 percent of Australia's electricity supply would come from renewable energy sources by 2020 by establishing the expanded national Renewable Energy Target (RET) scheme. Draft legislation on the design of the expanded RET was released in December 2008 and the final legislation was passed in August 2009.
The development of national wind farm guidelines will assist in wind farm planning and approval process and help address some of the barriers to wind farm development.
