Wind Energy Potential at Elevated Hub Heights in the US Midwest Region

Abstract

The US Midwest successfully generates wind power at a hub height of 80–90 m and the use of tall towers can reduce the wind energy cost. However, the lack of reliable wind data and production estimates at elevated heights hamper this effort. In this paper, wind resources and annual energy production (AEP) are studied using wind data up to 200 m above ground to estimate and validate AEP as a function of hub height at multiple sites. The AEP results show that energy production can increase by about 10% when the hub height is increased to 100 m. It also suggests that the optimal elevated hub height for a given region is not constant. A suitable site-specific height is desirable to minimize the levelized cost of energy (LCOE). Wind information from the National Renewable Energy Laboratory Wind Integration National Dataset (WIND) Toolkit is used as an alternative for estimating AEPs at elevated hub heights. This approach produced somewhat conservative results, confirming its use for wind farm planning purposes when measured wind data are not available.