A key phase in the planning process of a wind farm is measuring and analysing the wind speeds and wind directions at a proposed site. This data is used at various stages of the project, from determining what type and size of wind turbine would be most efficient, to deciding whether the site is viable in the long term. CWP Renewables is not linked with a specific wind turbine manufacturer, which enables us to model the turbine best suited to extract maximum energy from the wind at that site.
Wind Monitoring Masts
We generally install multiple wind monitoring masts onsite for a period of between 6-60 months. This ensures that we record a reliable data set per calendar year. This data is then compared to long term wind data acquired from BOM Automatic Weather Stations in order to predict the potential speeds for the site over the next 20 years.
Wind monitoring masts are usually 60-100 metres high, with wind speed measuring equipment (anemometers) and wind direction measuring equipment located at various heights on the mast. It is not uncommon to have six or seven anemometers at different heights to ensure we capture maximum wind data. These sensors are all electronic, and automatically transfer data back to the CWP Renewables offices every day, where it is verified to ensure the monitoring equipment is working correctly. The monitoring equipment is powered by a small solar panel unit that is connected to the mast.
Triton Sodar Sonic Wind Profilers
Unlike fixed wind monitoring masts, these trailer-mounted devices can easily be moved from location to location within the proposed wind farm area. This allows us to build up a more complex profile of wind speeds across the site. Each Triton Sodar emits a pulse of sound and records the returning echo to determine wind speed. These devices can record wind speeds up to 200m in height.
Once we have collected 6-12 months of wind data we will do an initial analysis using powerful computer modelling techniques. The software takes into account the contours and characteristics of the surrounding land, including any obstacles such as buildings, forests, and turbulence from the turbines themselves. From this analysis, a long term wind speed and a monthly average wind speed are forecasted for the site. This data informs selection of an appropriate turbine for use at the wind farm.
Example of a Wind Rose showing the speed and direction of the wind
Close up of a wind monitoring mast [anemometer]