Wind Energy

If one considers the fastest growing segment of energy production, the answer would be definitely wind energy production from renewable sources. Actually, wind energy currently represents the most common form of renewable energy in the world. Wind energy originates form solar energy. In its essence, it is transformed form of solar energy. The thing is that sun when radiates, unevenly heats different parts of the Earth, which as a result has different air pressures. Consequently, tendency to equalize air pressures creates wind. In some parts of the Earth, blow so-called constant winds and these areas are the most cost-effective in terms of wind energy production. Good positions for wind turbines installation are ocean coast and high seas. Offshore stands out as the best position because of the constant winds, however costs of installation and energy transport represent large obstacle for  such exploitation.

Wind Turbines Installation Capacity

In recent years, technology of wind turbines has significantly improved, especially in the terms of output power and efficiency. Power increase is achieved by increasing the size of the corresponding wind driven turbines. Currently the turbines able to generate strength between 3 and 5 MW are in exploitation. Due to the initial economic unprofitability and the vicissitudes of wind, wind turbine  installation is a privilege that only rich countries can afford. Currently, the price wind turbines is greater than the cost of thermal power per MW of installed power (wind turbine costs about 1000 € / kW of installed capacity, power plants and 700 € / kW). Nevertheless, owing to the development of technology, the difference between these two types of energy is decreasing. 

 

Predicted total installed wind turbine power in the world in megawatts (MW). From this chart, it can be seen that the total energy produced is negligible to the energy obtained from non-renewable sources of energy. Total installed capacity of wind power by the end of 2000 was predicted on 17,5 GW, which gives 0.05x109 kWh yearly disposable energy. Thus, this is indication that a wind turbine potential is not even remotely utilized.

At the moment, Germany is the leader in the production of electricity from the wind with approximately 9 GW, which is more than one third of the total installed capacity of wind turbines in the world. So many wind turbines in Germany, is the result of the policy of the German government, which stimulates installation of new capacity. Therefore, in 2001 the total installed has increased by 43.7%. Growth of installed capacity is observed in many countries, especially in Denmark, Italy and Spain. In Denmark, energy obtained from the wind contributes with 14% of the total electricity production and working progressively toward new capacities. The aim of Denmark government is that by the end of 2030, half of households meet the energy needs by taking advantage of winds. The United States, currently installed wind turbines that produce over 7 GW of electrical energy. However, this figure is not impressive at all, given the fact which wind potential world strongest economy has. This is the result of traditional American reliance on fossil fuels.

Wind availability atlas

The European Union and the United States have developed their resources atlases for wind speed and direction at 45 meters above ground level. Using these maps one can seen that almost 25% of territory of the European Union is suitable for installing wind turbines. Due to its geographic location, Denmark extents its wind potential since 1979. As a result, Denmark has today the most accurate information about the wind.

United States invested huge funds in building an atlas of potential wind energy for all of its areas. Almost 50% of the total area of the United States is extremely favorable for wind energy. The high altitude areas of west and southeast coast of United States, especially northern areas near the Canada, have percent of wind potentials up to 35%.

Not only does geographic positioning of wind turbines plays important role, but also and tower heights. For every 10 meters in height, price of the tower increases for 15 000 dollars. At the end, compromise between price and power should be made. Bigger turbines will give more energy, however, they are much more expensive at start.

Pros and Cons of Wind Energy

Advantages of wind energy are: high reliability of the plant, no fuel costs and no pollution. Bad sides are high construction costs and the variability of wind speeds (this means that it can not be guaranteed the delivery of energy). Households are more interested to small wind turbines up to 10 kW. They can be used as an additional source of energy or as a primary source of energy in remote areas. When used as a primary source of energy necessary to give it batteries (accumulators) in which energy is stored when generating more than spending. Large windmills are often installed in a wind park and through transformers connected to the power grid. When wind turbines are used off-grid (especially remote areas) as an additional source, in order to increase energy production, they should be used in combination with solar panels.