Comparison and validation of high-resolution techniques for spatial mapping of wind energy resources
3TIER, Inc., a renewable energy information services company, had a unique opportunity to test a variety of modeling techniques to assess the wind resource in a region of moderately complex terrain in the western United States, where multiple meteorological towers were deployed. Different towers and time periods were used to train the techniques and test them. The methods tested included:
* WRF alone, using different horizontal resolutions.
* WRF at coarser horizontal resolution coupled with a high-resolution downscaling model that makes boundary-layer flow adjustments based on high-resolution topography and land-use data.
* A linear flow model (Wind Atlas Analysis and Application Program, or WAsP), applied to areas surrounding the individual tower observations.
The tested techniques represent not only different approaches and representations of atmospheric physics, but also widely different computational costs. Therefore, cost-benefit is an important focus of the comparative analysis. The performance of the methods will be assessed based on standard metrics such as bias and root mean-squared error of wind speed and wind power. The performance of the different methods will be discussed, with emphasis on physical interpretation, as well as the cost-benefit perspective.