The extent to which the type of turbine you choose matters will depend on how much wind there is in your area. If you have wide open fields, low wind turbulence and a steady gust blowing pretty consistently then choosing a turbine that's right for this area will yield better results than using the same setup on a closed in, urban property. By the same token, the same turbine won't be as suitable in an area with a constantly changing wind directions and lots of obstructions causing turbulence.
What type of turbine should I choose?
Most parts of Australia get plenty of sun, and for that reason (as well as the fact that they require less maintenance), solar panels tend to be a far more popular and viable renewable energy choice in Australia - particularly for smaller domestic setups and in built-up areas.
Where they are installed, wind turbines tend to be used in rural and farm areas in southern and coastal parts of Australia where conditions are ideal for wind. Because of this, the Australian market is dominated by horizontal axis wind turbines (HAWTs) so if you're shopping locally your choices are likely to be limited. Vertical axis wind turbines (VAWTs) are constantly being developed and improved upon though, and are much more suited to roof mounting so we may yet see them appearing in neighbourhoods around Australia where solar's not a viable option.
HAWTs are typically mounted very high, at the top of a pole or tower where they can catch stronger winds than blow at ground level. These work best in large, open spaces where air turbulence is cut to a minimum and the wind blows consistently in one direction. The amount of power they can generate will depend on a few factors such as design, size and local wind speeds. To choose the right sort of turbine, you’ll need to have an energy target in mind - a goal of how much power you want to produce. In consultation with your supplier, you can then select an appropriate system based on your location and requirements.
Understanding power curves and rated power
Power curves are a common way for manufacturers to represent a turbine’s estimated output over a varied amount of wind speeds. Power curves show the estimated power generation for the turbine at given wind speeds. They also show the speed at which the turbine will cut in and cut out, and at what speeds it will perform at its peak. It's worth remembering that the curves provided by turbine manufacturers aren't always independently verified, and after testing many are found to overstate the amount of power they will generate at higher wind speeds.
Rated power, another common term used to describe a turbine’s output, represents a system’s generative capacity at a given wind speed - typically one common to the area. Unfortunately this wind speed may vary across different systems, and there is no standard which manufacturers are required to follow. For example, one system may be rated for 10w at 6m/sec while another may be rated for 10w at 10m/sec which is a significant difference. When comparing rated power of systems, be sure to factor this into your conclusions to ensure you're comparing apples to apples.