To provide a method for increasing windmill output by increasing a wind velocity hitting blades of an opposing translational blade windmills, regarding a method for improving windmill output by devising a blade orbit of the opposing translational blade windmill.

Output of a windmill is determined not from an absolute wind velocity but from a total velocity of wind and windmill blade moving velocities. Therefore, by increasing the total velocity, the windmill output can be improved. In a conventional translational blade windmill, blades are moved vertically to a wind direction but in an opposing translational blade windmill, blades perform unrelated orbital movement while performing translational movement.