This study aims to evaluate and quantify wind turbine performance aloft using a field-deployable tethered aerostat test platform, combining a lightweight horizontal-axis turbine, a conical diffuser, and synchronized onboard measurements of atmospheric conditions and electrical output. The platform is designed to enable higher-altitude operation (up to ~500 m), while the results presented in this study are based on field measurements up to ~60 m. Field measurements show that the mean wind speed increased from approximately 4.6 m/s at 20 m to 6.1 m/s at 60 m, producing a corresponding rise in electrical power output from ~37 W at the lowest recorded operating point (V≈2.6 m/s) to a maximum of ~52 W at around 50 m altitude (V≈6.1 m/s), consistent with the cubic wind–power relationship. The conical diffuser was additionally assessed under comparable wind conditions (~6.1 m/s) and provided a modest gain from 50 W to 52 W (≈ 4%) for the present geometry. These results indicate that height-adjustable lighter-than-air deployment can improve energy yield in low-wind regions without tower infrastructure by leveraging the vertical wind gradient, while highlighting that diffuser benefits are measurable but limited under the tested conditions and merit further geometric optimization and repeated trials.
Işilak et al. (Sun,) studied this question.