Energy is one of the most important aspects in our daily lives and as the world is geared towards conserving the environment, it is looking for alternative sources of energy such as wind and sun. When it comes to wind, there are different types of technologies that can be used in the generation electricity and one of them is the wind turbine. Wind turbine converts energy from the wind into electricity and comes in two types:
Horizontal Axis Wind Turbines
The horizontal axis wind turbines, abbreviated as HAWT features the electrical generator and the main rotor shaft, which must be turned towards the wind, at the tower top. Some of the small turbines feature a wind vane as a pointer while the large ones come with a wind sensor and a servo motor. They also feature a gear box that is responsible for rotating the blades at a higher rate on order to drive the generator.
The blades of the turbine are made to be stiff in order to prevent the high winds from pushing them into the tower. These wind turbines have been around for quite some time with the older ones featuring at least four blades. The modern HAWTs come with three blades and use computer controlled motors to be pointed towards the wind. They are efficient, reliable and more flexible with variable speed.
Vertical Axis Wind Turbines
The vertical Axis Wind turbines features the main rotor shaft In a vertical position and are most suitable for those places where the wind direction is variable. Unlike the HAWT, generators and the gear box of the VAWTs can be placed near the ground meaning that these are easier to access when it comes to maintenance.
With the VAWTs, the wind energy available is less since the speed of the wind is usually lower at low altitudes. The air flow as well as the presence of other objects near the ground can cause the production of a turbulent flow, which in turn produces vibrations leading to more maintenance and shorter lives.
How power is generated?
Now the most important question that how much power is generated with a wind turbine? Power is generated when the turbines move and transfer the momentum of the wind to the rotor blades, and then localize the energy into a single rotating shaft. The amount of power generated is influenced by quite a number of factors. The most obvious one is the wind. The speed as well as the force of the wind plays an important part when it comes to power generation. The other factor is the height. Higher altitude areas have more wind as compared to the low altitude areas as a result of different atmospheric factors.
Cost of Power generation
Apart from the natural aspects, the other factor that influences the amount of power produced is the rotor. It is important to note that the size of the rotor used in the wind turbine is proportional to the amount of the energy produced. This means that the users should invest in a large sized rotor for the optimum power generation.
It is also important to understand that the cost of purchasing and setting it up is higher in the long run.
As the whole world is going green these days, more and more countries are using wind turbines. If the 2009 year-end statistics are to be believed, 2% of the power that is required throughout the world is currently produced through wind turbines that is 340 TWh.