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Abstract:The feasibility of using crossflow runners as single rotors in vertical-axis wind turbines (VAWT) or as blades in horizontal-axis wind turbines (HAWT) is numerically studied. A computational fluid dynamics model is validated from data obtained in a wind tunnel. Three crossflow runners with different number of blades are tested. Values of drag, lift and torque coefficients are numerically obtained at different turning velocities. Power coefficients C p for crossflow VAWT and HAWT are calculated for different tip-speed ratios (TSR) and runner spin ratios (α). Since crossflow HAWT consume electrical energy for spinning the runners, the net power coefficient is estimated. Simulations indicate that a crossflow runner as a single rotor in VAWT should have a high solidity and work at low TSR. Crossflow runners working as blades in HAWT may achieve low drag to lift ratios but the C p is penalized by the amount of energy required for spinning the runners. The optimum working condition of crossflow HAWT is located within a narrow band of low TSR and α reaching C p values < 0.2 only.