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Eastern and Western Data Sets

The Eastern Wind Integration Data Set and Western Wind Integration Data Set were designed to perform wind integration studies and estimate power production from hypothetical wind power plants in the United States.

These data sets can help energy professionals such as transmission planners, utility planners, project developers, and university researchers:

  • Perform spatial and temporal comparisons of sites, including:
    • Geographic diversity
    • Load correlation
  • Estimate power production from hypothetical wind power plants, including:
    • Needs for storage based on wind variability
    • Potential transmission line loadings
    • Simple economic calculations comparing in-state versus out-of-state costs of delivered energy.

These data sets were NOT designed for:

  • Long-term average wind speed or wind power output
  • Absolute accuracy of wind speed or power output for a particular site
  • Use as the sole basis for a project investment.

Differences Between the Eastern and Western Data Sets

The Eastern Wind Integration Data Set was originally created for the Eastern Wind Integration and Transmission Study, and the Western Wind Integration Data Set was originally created for the Western Wind and Solar Integration Study.

The Eastern Wind Integration Data Set and the Western Wind Integration Data Set were created for very similar purposes and have the same period of record (1/1/2004–12/31/2006), but the data files and the methodology used to create them are not the same. The following table summarizes some of the differences between them.

Eastern Data Set Western Data Set
Produced by AWS Truepower 3TIER
Mesoscale Model MASS WRF
Number of Output Points 1,326 32,043
Size of Output Point 5 km2 to 160 km2 1 arc-minute2
Output Point Capacity (MW) 100 MW to 1,435 MW 30
Model Output Heights (m agl) 80 m, 100 m 100 m
Turbine Power Curves Three composite curves (each is the average of two or three commercial turbine power curves) Vestas V-90 3 MW

Wind Maps and Other Data

These data sets may not match the distribution of the wind resource shown on U.S. Department of Energy state wind maps. The state wind maps depict the distribution of long-term average wind resources, whereas these data sets were designed for use in wind integration studies that examine temporal profiles of wind and load.

These data sets are time-series data for 2004, 2005, and 2006. This means that if you are investigating an overall good wind site but, for example, 2004 happened to be a bad year for that site, then the time-series results for 2004 will likely reflect the poor resource during that year. Conversely, 1 year of data from this wind data set might show a good wind resource due to interannual variations, yet the long-term average resource may be lower. The goal of these data sets was for use in wind integration studies that examine wind profiles with load or other wind. The goal of the wind maps is to depict the distribution of long-term average wind resources. These time-series data sets and the wind maps were created for different goals and cannot be directly compared. Additionally, different techniques were used in the modeling for these data sets and the wind maps, and these will result in different modeling errors.

Even when similar models and techniques have been used, initial parameters into the model may have been different, resulting in different outputs. The goal for these data sets was to obtain broad, regional data sets that were consistent across a very large area. This means that specific regions may have been better modeled using different initial input parameters; NREL attempted to yield the best broad representation, which may have been at the expense of better accuracy in specific regions.