Developing a high‐resolution wind map for a complex terrain with a coupled MM5/CALMET system

Abstract

[1] This study investigates the wind energy potential in Hong Kong, a region with a complex terrain, by coupling the prognostic MM5 mesoscale model with the CALMET diagnostic model to produce high-resolution wind fields. Hourly wind fields were simulated for the entire year of 2004. The MM5 simulations were performed on a nested grid from 40.5 km down to 1.5 km horizontal resolution. The CALMET meteorological model was used in a domain that includes the entire Hong Kong region with a high horizontal resolution of 100 m. The MM5 model wind field (1.5 km horizontal resolution) output was input into the CALMET diagnostic meteorological model every hour along with an objective analysis procedure using all available observations. Verification was achieved through two steps. In the first step, the data from three meteorological surface stations that were not assimilated into the CALMET model were compared horizontally with the simulated wind fields. In the second step, the simulated wind fields were compared vertically with the vertical wind profile collected from two upper air sounding stations. The results of this study identified the locations of the highest wind energy potential in HK down to 100 m resolution.

Mesoscale Simulation of Year-to-Year Variation of Wind Power Potential over Southern China

“…The statistics information reveals the satisfactory ability of the models to reproduce the wind field. The results of upper sounding (please refer to Figure 3 for the location) comparison are also shown in Figure 4 and the results are also favorable, for details please refer to [25]. The model-error may be due to the limitation of CALMET model that its performance depends upon the density, frequency, and accuracy of the observations used as input for computing wind fields [29].…”

“…The shape (k) and scale (c) parameters can be calculated according to equations 4 and 5 respectively. In addition, for the analysis of the wind power potential, the corresponding percentage difference can be as large as 50% between considering the mean wind speed only and considering the wind speed spectrum [25]. This is because the power density is determined not only by the mean speed but also by the distribution of the wind speed.…”

“…The result of this is that the effects of the terrain and land surface characteristics on the meteorological fields are not always captured in the MM5 simulations. It also found that the coupling of MM5 with CALMET can resolve more realistic wind field [21,25]. Truhetz et al [26] investigated the influence of MM5's horizontal grid spacing on the resultant wind fields and found that the quality of the initial wind fields of the diagnostic model is of vital importance for the resultant wind field.…”

“…Almost 70% of the time in a year, the wind speed along coastal line is over the typical cut-in speed of the wind turbines. Wind power assessment should not only consider the mean wind speed, but also the wind characteristics and wind speed spectrum [25] and this is discussed in the following section.…”

Effects of urbanization on the land sea breeze circulation over the Pearl River Delta region in winter

“…However, simulating the small-scale flow field for the time scale of one year is very expensive and therefore simulation data is rare. Yim et al (2007;YIM2007 hereafter) used the MM5 to develop a highresolution wind map for complex terrain to investigate the potential of using wind energy in Hong Kong. In their study, hourly wind fields were simulated for one year from 2003 to 2004 by MM5 with four nested meshes from 40.5 km down to 1.5 km horizontal resolution using the 2003 HKPD land use data.…”