Q – Is there any topography data?

A – The data pack does not include a topographical map. Participants are expected to use a map from other data providers.


Q – Instructions indicate that participants are to provide production estimates for a one-year time period between Feb 2008 and Jan 2009. Is it normal that this period differs from the given met-mast measurement period (July 2011 to August 2012)?

A – Participants are asked to estimate energy productions in a 10-year period and one-year period set to Feb 2008 – Jan 2009. The one-year period differ from the period of the available met-mast data, but it allows comparison between the participants estimates and measured production data.


Q – The data pack provides a 16-year period of MERRA data. But instructions only require to calculate a 10-year estimate. Am I free to choose which period to use? Can I use the complete 16-year dataset and provide a 16-year estimate?

A – We ask for a 10-year period and the idea is that this should be representative for the long-term climate. Participants are free to use all of the supplied MERRA data or a subset of these. Please describe your procedure in the ‘Methodology Information’ page of the Excel reporting template.


Q – In the output template, to what measuring period does the Excel sheet ‘Per-turbine results‘ refer to?

A – The per-turbine results should be for the long-term period. We generally ask for long-term results except when otherwise specified.  


Q  – I have observed that there are important discrepancies between the two height levels wind vanes in the two masts samples. Could you tell me if the correct measures are from the higher wind vane?

A  – Some of the time series in the Excel sheet have somehow been corrupted compared to the original version. In particular, we warn about the wind-direction signals from the lower levels of each mast.


Q – Which air density value corresponds to the power and thrust curve of the V90 turbine? Is it 1.225 kg/m3?

A – The power and thrust-coefficient curves in the data pack are valid for normal turbine operation and air density of 1.225 kg/m3