Vertical Axis Wind Turbine: All You Wanted to Know
When it comes to the topic of the wind turbine, you probably think of turbines that look like aircraft propellers which are known as horizontal axis wind turbines. But there is another type of wind turbine which is still under development and seems to have a great potentiality to reduce the limitations of horizontal axis turbines.
Vertical axis turbines are easily distinguishable because of their vertical shape. Unlike the horizontal axis turbines, vertical ones come with a variety of shapes and designs.
This article will tell you about vertical axis turbine, its types, and why it can be an alternative to horizontal ones.
Vertical Axis Wind Turbine (VAWT)
A wind turbine cannot be a wind turbine unless it has few blades. Likewise, the horizontal axis turbines, vertical axis ones also have a set of blades. But instead of spinning horizontally, they spin vertically. So, the rotational axis of a VAWT is in the vertical direction, and that’s why it got such a name.
The engineers designed VAWT to make the turbine more economical and practical than the traditional ones. But unfortunately, the designs are not as effective as horizontal axis turbines. That's why this type of turbine is rarely used to produce a large amount of electricity.
Key Characteristics of Vertical Axis Wind Turbines
Types of Vertical Axis Wind Turbine
There are primarily two types of VAWT; Darrieus and Savonius wind turbine.
Darrieus Wind Turbines
Darrieus wind turbines look like an eggbeater, and that’s why they are also known as eggbeater turbines. This type was invented in 1931 by Georges Darrieus. It works with at least two blades that are vertically oriented and revolve around a vertical shaft. These turbines are high speed and low torque machine that generate AC electricity.
The generator of the turbine is located at the bottom of its blades. Blades are mounted with the help of a monopole. There are few guy wires connected to the pole that keeps the pole in place when the wind flow rotates the blades.
One of the main drawbacks of this kind of turbine is, it cannot start by its own. So, an external power source is required to make it rotate as the initial torque is quite low.
Some of the main features of the Darrieus wind turbines are –
Savonius Wind Turbines
Savonius wind turbines on the other hand, are low speed and high torque machine. Instead of using blades, this one uses scoops to capture wind energy. Each turbine has two or more scoops to produce electricity. The scoops turn around when the wind energy applies positive force on the front side of the scoops and a negative force on the back of the scoops.
Instead of using lift generated airfoil shaped blades, savonius wind turbines use drag, and that’s the reason why they don’t rotate the scoops faster than the wind speed.
Now let's have a look at some of the key features of savonius wind turbines.
Advantages of Having Vertical Axis Wind Turbines
VAWT has some characteristics that make people choose it over a HAWT for residential and business uses. Let's have a look at what are the benefits that a VAWT can bring to your home or office.
Disadvantages of Having Vertical Axis Wind Turbines
Although VAWTs have many benefits over traditional HAWTs, they have some limitations as well. You might be thinking about getting one for your home after knowing the advantages that it brings, but before making the final decision, it would be worth to know where this new innovation lacks the most.
So, Does it Worth to Invest in a VAWT?
Although vertical axis wind turbines don’t produce much energy like horizontal axis wind turbines, still they are great for small scale electricity production. If your energy requirement is moderate and you don’t have space for a HAWT, go with a vertical one without any hesitation. They suit best in limited space area and are easier to maintain.
Considering small scale energy production for urban areas, one cannot deny the effectiveness of using a vertical axis wind turbine. Despite having some limitations in a larger scale of production, engineers are trying to improve and develop vertical axis wind turbines which indicates its great potentiality.
Hopefully, this article was able to give you a clear understanding of vertical axis wind turbines and help you to decide whether you should get one for your household or not.