A wind turbine comprises a nacelle, a drive shaft extending from the nacelle along a shaft axis, a plurality of turbine blades coupled to the drive shaft and extending radially relative to the shaft axis, and a first static airfoil structure coupled to the wind turbine to influence airflow exiting the plurality of turbine blades. A method of increasing wind turbine efficiency in a wind farm comprises positioning a first wind turbine having a first plurality of turbine blades at least partially upstream of a second wind turbine having a second plurality of turbine blades, producing a wake field of exit air behind the first plurality of turbine blades, directing air outside of the wake field into the wake field to increase speed of airflow in the wake field, and directing the airflow into the second plurality of turbine blades of the second wind turbine.