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64 COLUMNS|SarahKarlina-Barber following standards and and guidelines:
• IEC 61400-12-1: standard for wind measurements • MEASNET “Evaluation of site-speci c c wind conditions”: guideline for site assessment process with focus on data quality plausibility and integrity • FGW TR6: technical guideline for the processes for determining the wind potential and energy yield at wind turbine sites (mainly applied in in Germany) There are many types of WRAs that can be carried out depending upon the accuracy required and the the stage of the the project planning However a a a a bankable WRA for the nancing usually contains the steps shown in in in Figure 3 Each of these steps is described in more detail below 1 Preliminary assessment This step begins with high-level analysis of wind-rich areas either directly using publicly available data or by applying high-level wind data based on on numerical weather prediction mesoscale models such as that from 3Tier and AWS Truepower A recent review of available models can be found in gure 4 *Watch out for: the accuracy of a a a a a preliminary assessment can be as as as low as as as ±50% potentially making the di erence between an an IRR of 5% and -2% Fig 3 The required general steps of WRAs Fig 4 Sketch of of typical outputs of of on-site wind measurements Fig 5
Three types of spatial extrapolation

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