Vertical Axis Wind Turbines

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How do vertical axis wind turbines work?

Even though the most common wind turbines in use today are based on a horizontal design, vertical axis wind turbines were actually the first design ever used for generating power. The early vertical axis wind turbines had a series of vertical sails that were mounted to a horizontal supporting structure. When the wind blew, these sails would cause the assembly to rotate and this motion would spin a central vertical shaft that could be used for various mechanical jobs like pumping water and grinding grain.

Over the years these vertical designs were replaced with the more common horizontal axis wind turbine because it offered a better efficiency than the typical vertical design. Even though this may have been true for centuries, several recent improvements in vertical wind turbine design may make up for this difference.

Vertical wind turbines are always adjusted to the direction of the wind

Horizontal axis wind turbines are very efficient in producing electricity, when they are turning. The challenge for a standard horizontal design is that it has to constantly adjust to face the ever-changing direction of the wind. It does this through the use of a rudder device and will always orient itself with the wind. The drawback to this scenario is that the turbine can't spin until it is oriented properly, and most winds change direction quite often. This means that even the best horizontal designs spend a lot of their time adjusting and less time generating power.

A modern vertical wind turbine doesn't use blades like the horizontal versions do. It typically has a series of cups or scoops that are designed to catch the wind and are mounted close to the vertical shaft. This makes these vertical wind turbines less obvious visually than the horizontal version and as a result they are more welcome in residential settings. When these scoops catch the wind, they rotate a vertical shaft that is connected to a generator that produces a current as a result of the rotation. This vertical wind power can then be used for your home, or fed into an electrical grid by a power company.

Advantages of vertical wind power

The advantage of a vertical axis wind turbine is that it can spin in a wind of any direction. Because its blades are vertical, they are always perfectly oriented to catch a passing breeze. This means it never has to adjust itself for proper wind positioning and will be generating power for longer portions of the day. It also has the advantage of being able to turn in lower velocity winds that many horizontal designs miss. This vertical wind turbine can even catch breezes that are too low a velocity to interest a horizontal turbine and use these to generate power. Considering all of these factors, the newer vertical axis wind turbines are attractive because even though they may generate less current when turning compared to a horizontal design, they are turning more often and this can make up the difference in their vertical wind power.

One final advantage to these vertical axis wind turbines is that since the shaft is vertical; the heavy generator can be mounted at ground level, which makes it easier to service. It also eliminates the need for a large tower to house the turbine like some larger horizontal designs require.