Windflow prototype provides another learning experience

14 December 2004

The Windflow 500 prototype has been undergoing testing since its initial placement at Gebbies Pass, working towards International Electrotechnical Committee (IEC) certification, the global standard for wind turbines.

"IEC certification is a rigorous testing and quality reporting programme that requires us to perform calibration work on every aspect of the turbine's performance from the strength of the blades to wind dynamics at the site. The ongoing measurements mean the turbine will be operated in a stop/start manner for some time yet, sometimes even with the blades being turned in odd directions to test the effect on them," Mr Henderson said.

At the moment the turbine is shut down for improvements to the lubrication system to the final stage of the gearbox. Last week it was discovered that an automatic shut-down at the weekend was the result of the smallest bearing in the gearbox giving way. "A neighbour rang at the weekend to say something didn't sound right, and shortly afterward it shut down so we had a fair idea something had come adrift," said Mr Henderson. "But it wasn't until the following Monday we were able to confirm this."

"The good news of course is that we are picking up these 'learning experiences' now while we are still testing on the prototype. This is why we've never wanted to 'run before we can walk'. In the scheme of things this bearing is a small detail and in no way detracts from the fundamental advantages of the design. Prototyping always throws up this sort of thing. Any industrial gearbox, particularly one as innovative as ours, will take a while to shake out all these issues."

"We believe that this particular issue was not due simply to high loads. Our investigations indicate lack of lubrication to that bearing. With Christmas upon us it's possible that the turbine will remain stationary until the New Year, which is unfortunate but does not really affect our testing program," Mr Henderson said.

"Overall, we are very pleased with the performance of the Windflow 500 and look forward to further enhancing the design to meet the most extreme conditions."