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There are also lift-based vertical-axis types like the "eggbeater" Darrieus from France (first patented in 1927.) Each blade sees maximum lift (torque) only twice per revolution, making for a huge torque (and power) sinusoidal output -- just like cranking on a bicycle -- that is not present in HAWTs. And the long VAWT blades have many natural frequencies of vibration which must be avoided during operation. For example, a 500-kW two-bladed vertical-axis turbine we have on site has two or three rotational speeds that must be gone through quickly to get up to operating speed and several modes within the operational band which the control must avoid. A well-designed HAWT has none of these problems.

VAWTs are very difficult to mount high on a tower to capture the higher level winds. Because of this, they are usually forced to accept the lower, more turbulent winds and produce less in possibly more damaging winds.

Guy cables are usually used to keep the turbine erect. They also impose a large thrust loading on the main turbine bearings and bearing selection is critical. Like all types of turbines, replacing main bearings requires that the turbine be taken down.

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