12 Meteorological data handling
12.1 Introduction ..................................................................................................................................... 2
12.2 Meteo Object: the data container .................................................................................................. 2
12.3 Meteo Object tab by tab .............................................................................................................. 3
12.3.1 Guide including online data description ..................................................................................... 3
12.3.2 Purpose ......................................................................................................................................... 7
12.3.3 Data .............................................................................................................................................. 8
12.3.3.1 Import setup .......................................................................................................................... 8
12.3.3.2 Calibration ........................................................................................................................... 11
12.3.3.3 Configuration ....................................................................................................................... 13
12.3.3.4 Data setup ........................................................................................................................... 18
12.3.3.4.1 The Add… button: adding & generating wind data at new heights ................................. 23
12.3.3.4.2 Remove tower shading: Add merged height ................................................................... 24
12.3.3.5 Time series ......................................................................................................................... 34
12.3.3.6 Frequency table .................................................................................................................. 36
12.3.3.7 Weibull ................................................................................................................................ 36
12.3.3.8 Turbulence .......................................................................................................................... 37
12.3.4 Graphics ...................................................................................................................................... 39
12.3.4.1 Time series ......................................................................................................................... 39
12.3.4.2 Weibull/Table ...................................................................................................................... 41
12.3.4.3 Turbulence .......................................................................................................................... 42
12.3.4.4 Rose view ........................................................................................................................... 42
12.3.4.5 Wind speed difference ........................................................................................................ 43
12.3.4.6 General XY graph ............................................................................................................... 43
12.3.4.7 Profile .................................................................................................................................. 44
12.3.5 Statistics ...................................................................................................................................... 46
12.3.6 Shear .......................................................................................................................................... 49
12.3.7 Mesoscale terrain ....................................................................................................................... 50
12.3.8 Report ......................................................................................................................................... 51
12.4 Meteo analyser .............................................................................................................................. 52
12.5 Meteo analyser: tab by tab ........................................................................................................... 53
12.5.1 Data: overview and selection of data .......................................................................................... 53
12.5.2 Graphics: Compare time series .................................................................................................. 54
12.5.3 Substitute: Perform data substitutions ........................................................................................ 55
12.5.4 Cross predict: WAsP vertical and horizontal extrapolation ......................................................... 56
12.5.5 Time variation: complete 1 year of data ..................................................................................... 59
12.5.6 Scaling create a new scaled time series using the Scaler ...................................................... 61
12.5.7 RSD verification .......................................................................................................................... 67
12.6 Flagging and data screening ....................................................................................................... 68
12.6.1 What is a flag? ............................................................................................................................ 68
12.6.2 Building conditions ...................................................................................................................... 69
12.6.3 Multiple conditions ...................................................................................................................... 72
12.6.4 Actions for flags .......................................................................................................................... 72
12.6.5 Flags in Meteo Analyser ............................................................................................................. 74
12.6.6 Import/Export flags ...................................................................................................................... 74
12.6.7 Showing flags in time series graph ............................................................................................. 75
12.6.8 Showing flags in time series table .............................................................................................. 76
12.6.9 Showing flags in XY graph and Wind Speed Relations graph ................................................... 76
12.6.10 Cleaning data with flags .......................................................................................................... 77
Introduction 2
© EMD International A/S www.emd.dk windPRO 4.1 September 2024
12.1 Introduction
Meteorological data is commonly supplied as time series, meaning large data amounts. There is a large range
of data sources, from local measurements to refined mesoscale model data. While local measurements often
have gaps or erroneous values and cover typically shorter periods, model data are usually available for long
periods back in time, whilst at the same time not being so accurate.
Different data sources complement each other, and efficient tools for comparisons and manipulations are
essential for preparing the data representing the long-term meteorological reality at the specific location. In
windPRO the tools for importing, screening, comparing, repairing and validating meteorological data can handle
most situations thanks to decades of development.
This chapter describes two main components:
The Meteo Object : For importing, screening, analyzing, synthesizing, merging, wake-cleaning (along with
PARK calculation), etc. data from a single source (mast, remote sensor, model output, etc.) with one or more
heights.
The Meteo Analyser : For comparison of multiple Meteo Objects data series (same station or different
stations), featuring cross-predictions, substitutions, gap filling and RSD (Remote Sensing Device) verification.
In both components, the SCALER function can be used. See details in Chapter 3 Energy on this comprehensive
model-based tool to transfer/extrapolate time series from one to another point for comparison and thereby
evaluation/calibration of the model.
Finally, it’s worth mentioning the online data service, whence data from all over the world can be downloaded
into a Meteo Object (subject to license conditions). It is probably the easiest-to-use and most comprehensive
service to be found in the business.
12.2 Meteo Object: the data container
The Meteo Object is the input object for wind data and other measurements or model data.
Input can be from the very simplest form:
input manually one wind speed (annual mean) in one sector together with Weibull k=2, and you can
calculate AEP based on just a simple mean wind speed and a Rayleigh distribution (Weibull with k=2)
to the very advanced form:
import measurements from a SODAR or LIDAR file with 25 different heights for a long measurement
period with high time resolution. The data files might even have changed format or units during the
measurement period. The Meteo Object importer can also read from compressed files, such as .ZIP
directly. Finally, it can read the NRG logger files (.RWD) directly (although this is processed through the
NRG data retriever software that must be installed).
Data from other loggers must first be converted to ASCII files (such as .txt or .csv) with the logger
proprietary software. Additionally, windPRO has an automatic filter for Zephir LIDAR data files so that
all definitions for all channels are filled out automatically.
A newer option is to load data directly from databases through an API.
The measurements can be used directly (i.e. without use of models) for AEP calculations in the calculation
module METEO. The most common method of use, however, is with MCP for long-term correction (see Chapter
3) and using these data and terrain information to generate a long-term representative wind statistic or time
series. These can then be used to calculate AEP with ATLAS, WAsP interface or (most commonly) the PARK
module.