Wind turbines are designed to convert wind into mechanical energy. The mechnical energy is converted into electricity that can be sent directly to the grid. The power generated by the turbine is proportional to the wind speed cubed. As an exemple, a wind turbine with a 6m/s wind will produce about 8 times as much electricity as a wind turbine with a 3m/S wind.
The average capacity factor (ratio of actual energy produced to the hypothetical maximum possible) of wind farms in Australia range from 25% to 40%. This compares with coal power stations that generally operate at around 85% of full capacity and gas plants whose capacity factor can vary from as high as 85% to less than 10%.
The Hornsdale Wind Farm capacity factor is expected to be higher than 45%, due to the exceptionnal wind regime in the region.
There are nearly 200,000 wind turbines across sites all over the world – many of them close to people’s houses.
Some 17 reviews of research literature conducted by leading health and research organisations from all over the world, including the World Health Organisation, Australia’s National Health and Medical Research Centre, the UK Health Protection Agency and the US National Research Council, have concluded that there is no published evidence to positively link wind turbines with adverse health effects.
Before it can operate, a wind farm has to demonstrate that noise levels at neighbouring residences will meet strict noise limits (35dB in rural areas, compared to background noises that generally range from 40 to 45dB).
These limits are designed to ensure that the noise from a wind farm is not intrusive for the average person.
A 2012 study by SKM on the economic benefits of wind farms in Australia found that, for every 50 MW in capacity, a wind farm delivered the following benefits:
– Direct employment of up to 48 construction workers, with each worker spending approximately $25,000 in the local area in shops, restaurants, hotels and other services (a total of up to $1.2 million)
– Direct employment of around five staff – a total annual input of $125,000 spent in the local economy
– Indirect employment during the construction phase of approximately 160 people locally, 504 state jobs and 795 nationwide jobs
– Up to $250,000 per year for farmers in land rental income and $80,000 on community projects each year.
If the project proceeds, on top of these benefits Neoen will implement a Community Fund in coordination with the Northern Areas Council. The fund’s objective is to support local initiatives on a yearly basis and for the whole life of the Wind Farm.
Neoen has undertaken several environmental studies including fauna studies before obtaining approval from the EPBC (Environment Protection and Biodiversity Conservation).
While wind farms are sometimes accused of threatening birds, an energy governance study done in Singapore has shown that wind farms actually kill 17 times less birds per gigawatt-hour of electricity produced than fossil fuel generation.
Studies show that wind farm are probably responsible for the death of 150,000 birds around the world every year, which is 400 times less than cars, 500 times less than pesticides, or 1200 times less than high-tension wires.