I visited the windfarm near Ravenshoe up on the Queensland tablelands. Ravenshoe, the near by town, is the highest place in Queensland, close to 900 meters above sea level. The windfarm is operated my Stanwell, and consists of 20 turbines, with a total output of 12 Mega Watts.

I meet up with the site manager, Bruce Chappell, and went through a generic site induction. Bruce then took us up to one of the windmills and we had a look inside. In the base of the tower is the windmill control logic and high power inverters. The windmills operate at 20 RPM, and generate 3 phase AC at a different frequencies to the grid supply, so the inverters convert the windmill AC to mains frequency. The AC then then fed into step up transformers where it is converted to 22kv and then 66kv for feeding into the grid.

The towers them selves act as cooling for the windmill. Air is circulated from the alternator at the top of the tower and through the inverters into the tower space where it is cooled by the steel tower walls.

The control logic takes care of yaw and blade pitch. There is a small weather station at the top of the windmill that gathers data used by the control logic. The windmills also log this weather data, as well as operating parameters ( blade pitch, power output, etc.). This data is sent to a near by office for recording and monthly reports.

Each windmill has a blade length of 22 meters, and the turbine center is 46 meters above ground level. While we were there the turbine was running at 20RPM, and I worked out the tips were traveling at 180kmh, give or take.

The windmills make almost no noise. From the visitors car park you could just hear the closest windmill( about 50 meters away ) as the blades swept past.

Up to July 2006 the windfarm generated 162.75 Gigga Watt Hrs of electricity, with a saving of approx 164,500 Tons of CO2 Gas.

You can click on the photos below to see the original picture. The originals are large, so please allow time for them to display.