Jacinta Bowler
The giant wind turbine had to be stopped as we walked underneath it.
Despite the hard hats we were wearing, there was a non-zero chance of something falling off, and so better to be safe than sorry according to Tim Ross, the asset engineer who had driven us up there.
“I’d say they’re running about half speed as what they normally do,” says Ross.
“That is the one thing that you forget, you go to work at the wind farm, and then you get up there and it always gets you – like wow, it is really windy.”
Part of a wind farm around an hour and a half outside of Adelaide, the turbine sits on a ridge and towers another 90 metres in the air. Then the three huge, perfectly balanced blades – add another 45 metres.
You have to crane your neck to see the top, which, if you need to get up there, requires a ladder, or the one-person elevator inside the tower. This – according to Ross – is “super wobbly” and a frightful journey, but significantly preferred to taking the ladder up what would be the equivalent of a 30-storey building.
“The turbines are never locked in place unless there’s maintenance, and if you can feel the slightest breeze the turbine will start spinning,” says Ross.
“It takes about three metres a second of wind – so a pretty light breeze – in order for them to start generating electricity. And then they’ll get faster and faster until about 15 metres a second.
“Then if the wind gets seriously fast, like in a storm, they’ll pause so they don’t run over speed and cause any damage.”
This doesn’t stop the blades from bending though.
On the ground, we saw some damaged blades are basically dead straight. But staring at the ones moving far above us it was obvious that they were curved backwards towards the tips.
Ross says that the wind is so powerful – even on a day with a slight breeze –the fiberglass blades bend back between 5 and 10 metres.
Although there’s an idea of a low frequency noise, we didn’t hear much when we were up there. Barely discernible under the sound of the wind was a gentle ‘womm’ as the blades turned.
As we drove away through yellow canola fields and grass land, we got one last glimpse of the 43 turbines on the ridge slowly spinning in the wind.
Together the 11-kilometre line of turbines generate an astonishing 130 MW of power – enough to run about 80,000 homes.
As long as the wind keeps blowing.