One of the reasons may be a problem with "disabling" vertical turbines during high winds. With properller-like turbines, blade can rotate to move edge-on toward

One of the reasons may be a problem with "disabling" vertical turbines during high winds. With properller-like turbines, blade can rotate to move edge-on towards the wind direction or move parts of blades in the opposite direction, so that the overall torque in each blade is zero regardless of the wind speed.