"GASP Global" is short for "GASP 1.0 - Global of Atlas of Siting Parameters". It is released with windPRO 3.5+ as a global atlas dataset with the following key features:
Global 250m wind resources, siting parameters & turbine design classification
Builds on DTU GWA (Global Wind Atlas) datasets and EMD's Load Response technology
Coordinate system: Geographical coordinates (EPSG: 4326) in original data
Version: 1.0
Validation and Usage Notes
How accurate is your resource prospecting based on GASP data in windPRO or windPROSPECTING? We have prepared a small validation note - based on data from 241 high quality meteorological towers - that gives you a first hint on bias and uncertainty - read more - HERE.
Need turbulence intensity instead of the GASP windspeed standard deviation? We have prepared a small pdf that describes how to convert from wind speed standard deviations to turbulence intensities - and how to use the two model parameters (A) and (B) to derive the turbulence intensity at any wind speed - read more - HERE.
How is the GASP shear calculated? The shear values from GASP are estimated using the DTU-LINCOM flow model. According to DTU, this was the best "local" source of shear given the models available during development of the GASP dataset (neutral atmospheric stability assumed, so the reported GASP shear is representative for "higher" wind speeds). Another option would have been to estimate the shear using the WAsP model (with default or custom-specified atmospheric stability parameters). However, if you are interested in "WAsP-shear" values, it is perfectly possible to derive those directly (but manually) from existing GASP annual average wind speeds in 50m, 100m and 150m [parameter: wsp]. The "WAsP-shear" is currently not included in the GAsP dataset version 1.0, but under consideration for a future dataset update.
Availability from EMD's software
Wind Resouces in 100m height at Lillgrunden, Sweden. GASP data accessed through windPRO 3.5.50yr Extreme Wind Speeds in 100m height at Tasmania, Australia. GASP data accessed through http://www.windPROSPECTING.com platform.50yr Extreme Wind Speeds in 100m height at Danish Offshore Wind Farms. GASP data accessed through the EMD-API platform, http://api.emd.dk
windPRO: In 'Data' menu click 'Siting parameters (GASP etc)' to access the download tool. Data is loaded into a result layer with a .siteres file acting as the data-container.
The .siteres file can be used in PARK, Site Compliance, Load Response and Optimization calculations.
windPROSPECTING: GASP data is available through the data-tab named 'Site-prospecting'. Free access to windPROSPECTING - here.
windprospecting offers spatial view of omnidirectinal parameters and detailed point-data with directional results and statistics.
EMD-API: Read more at the dedicated wiki-page for our Global Atlas Data Services - here. If you are accessing the GASP data from within the EMD-API, you will use the parameter group-names in order to request specific data-packages [resource-omni, resource-sector, siting-extremes, siting-fatigue-omni, siting-fatigue-sector, turbine-fatigue, turbine-fatigue-recommend, turbine-extreme, turbine-extreme-recommend].
Parameters and Dimensions
As seen from the tables below, a very wide range of omnidirectional and sectorwise parameters are available from GASP. These parameters are divided into four main categories:
Wind Resources / Atmospheric Parameters
Siting Parameters – Fatigue
Siting Parameters – Extremes
Turbine Design Classification - with recommended turbine class. 3 separate aeroelastic models are used as representative for the 3 heights
50m: WindPACT 1.5MW
100m: NREL 5MW
150m: DTU 10MW
The tables below provides an overview of all parameters available and at which dimensions that they are available. We have used the following dimensions for the GASP parameters: The first four (longitude, latitude, height and sector) are used for the basic parameters; the last three (ws_class, iec_class and turbine_component) are used for the turbine design classification - and are releated to the IEC61400-1 code and the aeroelastic load model. Please note that not all dimensions are relevant or used for every GASP parameter.
Table: List of dimensions in GASP data.
Dimension
Abbreviation
Unit
Range
longitude
lon
deg
180 to -180
latitude
lat
deg
90 to -90
height
h
m
50,100,150
sector
s
deg
0,30,...,330
ws_class
wcl
I,II,III,T
iec_class
iecc
IA+, IA,...IIIC
turbine_component
tc
0,1,2,3
Parameters: Wind Resource
The two tables below show the GASP parameters for wind resource data divided in omnidirectional data [resource-omni] and sectorwise data [resource-sector].
Wind distribution: A (Scale) parameter in Weibull distribution
m/s
lon, lat, h, s
weib_k
Wind distribution: k (shape) parameter in Weibull distribution
lon, lat, h, s
sector_freq
Wind distribution: Sector frequency
lon, lat, h, s
wsp
Wind speed - annual average
m/s
lon, lat, h, s
wpd
Wind power density – annual average
W/m2
lon, lat, h, s
air_dens
Air density (annual mean/average)
kg/m3
lon, lat, h
elevation
Air density (annual mean/average)
kg/m3
lon, lat, h
Parameters: Siting Classification - Wind Extremes
The table below shows the GASP parameters for the extreme event data [siting-extremes]. Please note that this extreme data is only available as omnidirectional parameters.
The two tables below show the GASP parameters for the siting-fatigue parameters - given either omnidirectional or sectorwise data-requests [siting-fatigue-omni, siting-fatigue-sector].
Turbulence offset parameter from IEC 61400-1 (ed4) – P90
m/s
lon, lat, h, s
Parameters: Turbine Design – Loads
The four tables below show the GASP parameters for the turbine design classification. The two main groups are fatigue and extreme load cases, divided into four data-groups so requests is possible for turbine load indexes and iec class recommendations: [turbine-fatigue, turbine-fatigue-recommend, turbine-extreme, turbine-extreme-recommend].
Table: Turbine Design – Fatigue [turbine-fatigue]
Variable
Description
Unit
Dimensions
flsidx
Load index for the fatigue limit state
%
lon, lat, h, iecc, tc
flsidx_w
Load load index for the fatigue limit state with wakes
IEC Class Recommendation – ultimate limit state (ULS) – text
lon, lat, h
License and Attribution
The data is available through a Creative commons 4.0 by attribution license (CC BY 4.0). Please accept the license conditions and use a proper attribution when using this dataset, such as:
GASP 1.0: Global Atlas of Siting Parameters 1.0 by EMD and DTU, is a free dataset accessible via
EMD (windprospecting.com, windPRO & EMD-API) and DTU (globalwindatlas.info, science.globalwindatlas.info & data.dtu.dk).
License: CC-BY-4.0
Acknowledgement
GASP is the result of a BIG collective effort by many people at: EMD International A/S & DTU Wind Energy, with overall project manager Xiaoli Larsén (DTU)
Develoment and integration of this dataset into EMD services was done through the GASP project which is co-funded by the EUDP and the Danish Energy Agency
↑ 1.01.11.21.31.41.5Note: This parameter is windspeed standard deviation. It can be converted into a turbulence intensity - see more at the usage note section above.
