There are several types of wind turbines to take into consideration for those looking for a sustainable source of power. On a large scale, wind farms are a more efficient and consistent alternative to solar energy. As such, a lot of research and funding has gone into designing new types of wind energy turbines that can help us make the switch to a more sustainable lifestyle as quickly as possible.
Affordability, efficiency, and reliability are just some of the key features for both manufacturers and consumers. Below, you’ll find the different types of wind turbines you can purchase right now.
Types of Wind Turbines According to Scale
Depending on their scale, wind turbines can power anything from a recreational vehicle to thousands of homes. Before buying one, consider the following possible choices:
- Micro wind turbines. These machines range from 20W to 500W and are commonly used to power up sailboats and other recreational vehicles. Although they are not sufficient to fulfill the electricity requirements of a home, they are still fairly powerful compared to most small-scale solar panels.
- Residential wind turbines. These turbines are designed to power a single home and can therefore range from 400W to 100kW, depending on your specific needs. Before buying and installing a residential wind turbine, you should always calculate the average electricity consumption in your home and select a product that matches your requirements.
- Utility-scale turbines. From the GE 1.5 MW model to the majestic MHI Vestas V164, with its output of 9 MW, utility turbines can generate tremendous amounts of electricity – enough to power entire communities and even small cities.
Different Types of Wind Turbines According to Design
Turbines can vary in terms of design and, implicitly, the way that they utilize the aerodynamic force of the wind. Each of the three types mentioned below have their own advantages and disadvantages, so it’s essential that they are chosen for the right applications.
Horizontal-Axis Wind Turbines
Currently the most widespread model, the horizontal-axis wind turbine is easily recognizable by its very tall tower, horizontal shaft, and large blades. With this model, the shaft is parallel to the ground, while the blades turn to face the wind for optimal efficiency.
When the wind is strong enough to start pushing the blades, these begin to move and cause a rotation in the shaft. At the end of the shaft, a gear is interlocked with a generator that produces electricity and sends it into the power grid. If and when the wind starts blowing from a different direction, a built-in motor repositions the nacelle so that the blades always face the correct side.
The advantages of a horizontal-axis turbine compared to other types of wind turbines include:
- It is mounted on a very high tower, which allows it to take advantage of stronger winds.
- Can even be used in forests if built above the tree line.
- The turbine blades can be pitched during a storm, thus reducing any potential damage to the machinery.
- Can be placed in off-shore locations or on uneven land.
The disadvantages of a horizontal-axis turbine are:
- The structure can take massive proportions, which makes it difficult to transport and to install.
- Performing repairs in case of damage can be difficult and costly.
- Cannot take proper advantage of winds that are close to the ground.
Vertical-Axis Wind Turbines
The main distinction between horizontal-axis and vertical-axis turbines is the positioning of the blades. In the case of the latter, the blades are connected to a vertical pole and the entire mechanism is much closer to the ground. While the shaft, blades, and generator are slightly elevated above the ground, there is no need for a tower to lift them up in the air.
As compared to different types of wind turbines, a vertical-axis model presents the following notable advantages:
- It works regardless of the direction of the wind and does not need to be turned for optimal efficiency.
- It is much smaller than most horizontal-axis turbines, which means it also has lower construction and transportation costs.
- It is easier to maintain than a horizontal-axis turbine.
- Can take advantage of lower winds and is, therefore, best suited for hilltops, passes, and mesas.
The disadvantages of vertical-axis wind turbines are:
- The blades might experience drag, which reduces efficiency.
- Overall less effective than horizontal-axis and new types of wind turbines that generate more energy.
- Because they are closer to the ground, the wind is more turbulent and more likely to cause damage to the machinery.
- Unlike horizontal-axis turbines, these sometimes need energy to start.
Ducted Wind Turbines for Dense Urban Areas
Among new types of wind turbines, this model is perhaps the most promising. Ducted wind turbines address the problem that has prevented this technology from being implemented in densely populated areas such as cities. They look nothing like traditional turbines, but they still work in virtue of the aerodynamic force of the wind.
As their name suggests, these turbines essentially consist of air ducts placed along the side of a large building, with one opening onto the roof. Their design allows them to use the airflow that passes upwards of the building’s side and that moves a built-in rotor in order to generate electricity.
Although the efficiency of these new types of wind turbines is yet to be properly tested, the advantages they present thus far include:
- They can be used in densely populated areas such as very large cities.
- They are barely noticeable and have little impact on the aesthetics of a building.
- They avoid altogether the transmission losses that come with centralized energy generation because they allow the on-site production of electricity.
The main disadvantages of ducted wind turbines are:
- They cannot be used for houses.
- The wind must blow in the right direction for them to work.
- As a new model, this type of wind turbine is not yet properly tested for efficiency.
While new types of wind turbines are still being researched and developed, horizontal- and vertical-axis turbines remain the two most cost-effective turbines for the time being. There are many factors to consider before installing either one of these machines in your backyard or community, but once you choose the best type, you’re already one step in the right direction towards sustainable energy.