Among all the renewable power sources, wind energy is the fastest growing industry in the past few years. This is because the ecological benefits that come with this technology and the falling costs of the wind turbines.
Wind use is one of the oldest and well known practices that mankind takes advantage of. It is abundant, it’s free, it doesn’t lead to any kind of pollution or any climate anomalies.
Wind power has the capabilities that none of the traditional power sources has. Operational costs ( or in this case the lack of such ) make this technology appealing to the investors.
Wind is a natural phenomenon that can be explained as moving air masses, that possess speed and direction. It’s generated by the difference in heat on the surface of our planet. The hot air rises and creates a place with low atmospheric pressure that is filled by air with lower temperatures ( higher density ). Bigger differences will result in stronger winds.
This renewable energy source possesses certain characteristics, such as speed, direction, turbulence, etc. The average speeds changes with the altitude and so does the direction.
Winds have global and local importance.
The global winds are dependent on the global characteristics of the climate. They are more constant and change only with the seasons.
Local ones are dependent on the local climate changes, such as mountains, lakes, seas and other such things. The mountain masses are interesting models for creating air currents. One such example is the formation of air currents around the south oriental mountain slopes. When the slope is heated up by the sun, it rises the temperature of the air around it, thus, lowering its density and raising it towards the peaks. ( Analog models for air currents happen around the sea masses. )
Over the night hours, the direction of these winds change.
Because of the rotation of the Earth ( The Coriolis Effect ) and the cooling that happens when moving from the equator towards the poles, global winds and their direction, for example between the 30 parallel and the 60 north parallel, are gaining speed from northwest to southeast.
The regions around the equator ( at 0 latitude ) are heated by our sun more than other locations on our planet. The hot air raises way above the cold one, until it reaches around 10 km ( about 6,2 miles ) above sea level. After that it moves towards the North and South Pole. If Earth was not spinning, the hot air would go directly to the North Pole, cool down and come back to the equator.
The landscape of the terrain and the topographic profile of the area close and far also play a huge role affecting the whole dynamics of the system.
The key factors, depicting the possible use of the renewable energy are:
- The meteorological conditions.
- The way of conversion of the kinetic energy to electrical one.
- Its use in the electrical grid.
- The economic effectiveness of wind energy.
The energy resources ( potential ) of wind can be rated in three areas:
- Natural resources ( Theoretical potential ).
- Resources, converted to practical use ( Technical potential ).
- Economic resources.
Natural resources are depicted by the kinetic energy.
The energy, which is in accordance with the laws of nature, and is converted to practical energy used for commercial use, correlates to its technical potential.
The part of the technical potential, which is transformed by economic costs, corresponds to the economic potential of the energy resource.
The effective use of that renewable energy, with wind generators and turbines working independently or combined as a wind farm, requires professional contemplation. Every inaccuracy may lead to over 200% rise in costs for the annual electricity. This sensitivity about the details and the choice of the generator is due to the fact that the power of the wind turbine depends on the speed of the wind. ( Which explains why the location for building such a structure should be predetermined and well thought of. )
Technical problems while using wind energy:
The consistency and direction of the wind pose some of the challenges with this technology. Wind concentration also plays a vital role in the industrial use of this energy. One of the best ways to utilize this is with the help of large wind turbines, placed upon stable towers ( pylons ). The power of the wind turbine is depicted by the diameter of the rotor. With bigger diameter, the turbine can cover more area and thus a bigger quantity of air that travels true.
Reasons for the choice of wind turbines with larger diameter:
- Economically it’s more profitable to construct turbines with a large diameter. In this case, the cost expense for the construction, the connection with the electrical grid, and the roads that lead to the turbines are cheaper.
- Large wind turbines are also ideal for offshore use, where they can take advantage of the wind energy with fewer obstacles in the way. ( Like mountains, trees, buildings etc. )
In regions where there is no available terrain for the construction of a wind farm.
Effects on the environment:
The cool thing about wind energy is that it doesn’t rely on fuel and emit way less air pollution than traditional power sources. Let’s not forget that power stations and power plants rely on water for cooling, water which humans need to live and also stuff that’s running out. In fact, 14 million liters of water are used every year in conventional ways of generating energy; meanwhile, wind turbines use none.
There has been some backlash about how wind turbines affect birds and bats.
To put it into perspective, the glass windows on buildings are actually much more detrimental to bird populations. Wind turbines do still affect birds, so, moving forward with the placement of wind turbines, it’s important that we focus on putting them outside of bird migratory patterns.
As for bats, scientists have been experimenting with special types of paint that actually show up for bats during echolocation to help avoid collisions. This is another example how scientists are continually making wind energy better for the environment.
The bottom line is:
Surprisingly, wind turbines are able to compete with other energy sources, when it comes to cost per energy output. Though, has come after years of improvements in efficiency and technology.
Chances are that with time, this technology is only going to get better and better.