GASP Global

Introduction

"GASP Global" is short for "GASP 1.0 - Global of Atlas of Siting Parameters". It is a global atlas dataset with the following key features:

• Global 250m wind resources, siting parameters & turbine design classification
• Builds on GWA3.0 and other sources
• A joint project by EMD and DTU

Dataset Overview

• Spatial coverage:
  • Near global (all land areas from N80 to S58)
  • Offshore areas are covered up to 200 km from the coastline
• Resolution:
  • Horizontal: 250m in grid resolution
  • Vertical: 50m, 100m and 150m as vertical levels
• Data-type: Atlas
• Coordinate system: Geographical coordinates (EPSG: 4326) in original data
• Version: 1.0

Availability from within EMD software

• windPRO: Click 'Data' -> '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.
• windPROSPECTING: GASP data is available through the data-tab named 'Site-prospecting'. Free access to windPROSPECTING - here.
• 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 the Global Atlas of Siting Parameters (GASP). These parameters have been divided into four main categories:

1. Wind Resources / Atmospheric Parameters
2. Siting Parameters – Fatigue
3. Siting Parameters – Extremes
4. Turbine Design Classification - with recommended turbine class

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 Resources

The two tables below show the GASP parameters for wind resources data, given omnidirectional data [resource-omni] and sectorwise data [resource-sector].

Table: Resource / Atmospheric Omni-directional Parameters [resource-omni]

Variable	Description	Unit	Dimensions
weib_A	Wind distribution: A (Scale) parameter in Weibull distribution	m/s	lon, lat, h
weib_k	Wind distribution: k (shape) parameter in Weibull distribution		lon, lat, h
wsp	Wind speed - annual average	m/s	lon, lat, h
wpd	Wind power density – annual average	W/m2	lon, lat, h
air_dens	Air density (annual mean/average)	kg/m3	lon, lat, h

Table: Resource / Atmospheric Sector-wise Parameters [resource-sector]

Variable	Description	Unit	Dimensions
weib_A	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.

Table: Siting Parameters – Extremes [siting-extremes]

Variable	Description	Unit	Dimensions
air_dens_p98	Air density at 98th percentile of wind speed	kg/m3	lon, lat, h
wsp_50yr	50yr extreme wind speed: Average	m/s	lon, lat, h
gumbel_alpha	50yr extreme wind speed: Gumbel distribution – alpha parameter	m/s	lon, lat, h
gumbel_beta	50yr extreme wind speed: Gumbel distribution – beta parameter	m/s	lon, lat, h

Parameters: Siting Classification - Wind Fatigue 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].

Table: Siting Parameters Omnidirectional – Fatigue [siting-fatigue-omni]

Variable	Description	Unit	Dimensions
shear_exp	Wind shear exponent (calculated using LINCOM model) - Mean		lon, lat, h
flow_inc	Flow inclination (calculated using LINCOM model)	deg	lon, lat, h
terrain_ic	Terrain complexity as defined in IEC 61400-1 standard (ed 4)		lon, lat, h
sigma_P90A	Turbulence slope parameter from IEC 61400-1 (ed4) – P90		lon, lat, h
sigma_P90B	Turbulence offset parameter from IEC 61400-1 (ed4) – P90	m/s	lon, lat, h
sigma_P90U15	Turbulence P90 at a fixed windspeed of 15 m/s	m/s	lon, lat, h
air_dens	Air density (annual mean/average)	kg/m3	lon, lat, h

Table: Siting Parameters – Fatigue [siting-fatigue-sector]

Variable	Description	Unit	Dimensions
shear_exp	Wind shear exponent (calculated using LINCOM model) - Mean		lon, lat, h, s
flow_inc	Flow inclination (calculated using LINCOM model)	deg	lon, lat, h, s
sigma_meanA	Turbulence slope parameter from IEC 61400-1 (ed4) – Mean	m/s	lon, lat, h, s
sigma_meanB	Turbulence offset parameter from IEC 61400-1 (ed4) – Mean	m/s	lon, lat, h, s
sigma_P90A	Turbulence slope parameter from IEC 61400-1 (ed4) – P90		lon, lat, h, s
sigma_P90B	Turbulence offset parameter from IEC 61400-1 (ed4) – P90	m/s	lon, lat, h, s

License and Attribution

The data is available throguth 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, by EMD and DTU, is a free dataset accessible via windprospecting.com, windPRO and EMD-API.

Acknowledgement

• 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

External Links

• GASP Project Home-Page at DTU - here