The modelling work is based on the industry-standard Danish RISØ "Wind Atlas Analysis and Application Programme," or WASP, model. But it is more sophisticated for demanding situations, Dr Coppin says. WASP, he explains, takes a mean-field linear approach that can adequately model smooth terrain, but it can not effectively cope with the separated flow turbulence generated by steeper slopes. It does it quite well within its limits, says Coppin, adding that the CSIRO work has produced a linear model for steeper sites and turbulence called Raptor.
Coppin's Wind Flow group, based in Canberra, has used Raptor to assess the site of the 5 MW Crookwell wind farm (Windpower Monthly, September 1997), currently under construction. The model was used by wind prospectors at a regional level to isolate hot spots of wind potential and has been validated through an extensive monitoring programme in the Crookwell area, says Coppin.
The wind group is now developing a non-linear model to account for turbulence on steep terrain. When complete in about 12 months, Coppin hopes the new model, which is yet to be named, can be used by the entire wind power community.