High-Altitude Wind Resource Potential for AWE in Portugal

Airborne wind energy (AWE) systems aim to harvest wind energy at higher altitudes than conventional technology. To dimension the system and assess the potential power one can extract from a given location, its wind resource, namely the wind speed vertical profile, has to be characterized. The vertical profile is influenced by the location’s topography, surface roughness, and atmospheric stability conditions, which are often disregarded in AWE studies. This paper aims to assess the impact of these factors in wind speed and power vertical profiles for a region of Portugal and, by doing it, estimate the wind resource for a potential AWE exploration. One concluded that harnessing high-altitude wind energy was more advantageous in onshore locations; in addition, stable atmospheric conditions provided larger wind speeds and, therefore, the wind power available was larger. For the studied region of Portugal, one projected a maximum sustained wind speed of 18 m/s at a height of 250 m. Finally, one studied the wind resource for three specific locations, potential sites for AWE exploration employing a “Drag-mode” system, and verified that the rural site of Alenquer presented the best wind resource.