Comparison of wind simulation models for assessment of wind energy potential: a case of Maputo bay in costa do sol beach area

The majority of the Mozambican population lives in the rural areas with little or no access to clean energy. The main source of energy then becomes inevitably traditional biomass in the form of firewood. Exploitation of renewable energy resource would boost the proportion of the population with access to electricity. Mozambique coastline has unexplored wind resources that could contribute to the national electricity grid or to other applications. Wind is one of the primary energy resources that can be harnessed to provide electricity to the end-users. This study is based on comparison of wind simulation models for assessment of wind energy potential specifically in Maputo Bay in Costa do Sol beach area. The wind speed data measured at the Costa do Sol Meteorological Station were used as inputs to WAsP model, while 3Tier model uses geographical coordinates of the Meteorological Station as its inputs for preliminary assessment of the wind resources. The outputs parameters generated at 50 m hub height with 3Tier were the following: AMWS: 7.6 1.5 m/s, AMWD: ENE, scale A: 8.57 m/s, and scale k: 2.37, while for WAsP from OWC were: AMWS: 6.12 m/s, AMWD: SWS, scale A: 6.8 m/s, and scale k: 2.07. The results of the study reveal that the outputs generated by 3Tier model are too coarse because they do not consider small scale variations caused by physical effects (obstacles, roughness, etc.), while WAsP gives much better accuracy because it considers data measured on the ground, therefore, was selected for detailed resource assessment. In Costa do Sol, the estimated values by using WAsP model were: AMWS (4.73 to 6.33 m/s); PD (113 to 278 W/m2); AEP (0.857 to 1.911 GWh), and Vestas 850kW was selected for wind mapping and energy estimation which was modeled and simulated at 50 m hub height.