Author : Matteo Aristei
2019, August 3rd
In recent years, many countries have decided to renew their energy supply . The goal is to reduce the use of non – renewable and polluting sources .
In the future, in fact, electricity should be extracted as much as possible from wind, sun and water .
Renewable energy means resources that are available almost to infinity, whose extraction does not damage the environment and are : sun, water, wind, geothermal energy and bioenergy .
In addition to protecting the environment, we should also be concerned about the development of renewable energy . Until 2020 the percentage of renewable energies should rise to 35 % of current consumption .
Geothermal energy is a technical term for the distribution of heat in the earth . We also speak of terrestrial heat . The deeper you go into the earth, the warmer it is . Scientists estimate that the temperature at the centre of the earth ranges from 4800 to 7700 degrees Celsius . The heat is obtained from heat pumps near the surface of the earth ‘s crust .
The heat inside our planet is available day and night . It can be used for both heating and current production . If there were no problems with drilling techniques, geothermal energy could cover the entire energy needs of a country .
Unfortunately, in various countries, hundreds or even thousands of meters in depth must be drilled to reach a sufficient temperature level . The costs of geothermal energy are therefore very high . Moreover, in some places there are problems with aquifers . Other countries are, for geological reasons, in one of the best locations, such as Iceland, which covers most of its energy needs thanks to the heat coming from within the earth .
The sun is a free source of energy and sunlight is available almost unlimitedly . So – called photovoltaic systems can convert sunlight into electricity . When sunlight meets a photovoltaic cell, it can convert light into energy . Often these systems are installed on the roofs of houses or in the fields . With a small solar system, owners of private homes can also heat their own running water or manage their heating independently .
By means of this, homeowners are more independent of electricity prices but of course they have to pay for the installations of the plants . The production of electricity with solar systems is mostly suitable for regions where there is not much sun . The amount of energy is independent of the number of hours of sunshine .
Much of the energy that allows us to live comfortably is not infinite and is running out . Moreover, it often pollutes a lot . This is why renewable energy is needed, that is, that does not end and does not pollute . Like the wind, created by the wind .
Let ‘s find out what we talk about when we discuss renewable sources, what wind energy is and how it can be exploited .
Wind energy, as its name implies ( Aeolus, the god of wind ), is a type of energy derived from the force of the wind, which is converted into labor – power ( often in the form of electricity ).
Since ancient times the passing of currents has been the ally of men to move ( the sails blown by the wind allowed to navigate easily ) or to move objects of production ( the rotating blades of windmills, for example, moved the millstones to crush the wheat and make flour ). Nowadays, however, it was thought to use the force of air to produce electricity .
Between the nineteenth and twentieth centuries, various scientists focused their studies on the exploitation of wind for energy purposes . The result of their studies is that today, most of the wind energy is produced by turbines and wind turbines .
How do you convert wind power into energy ?
Electric energy is obtained from turbines that transform the movement of the blades moved by the wind into electricity .
As in paper swivels, so the wind moves the large wind turbine blades creating kinetic energy ( ie the energy generated by the movement of a body ).
The blades are connected to a rotor, in turn connected to a ” shaft ” 1 ( placed in the pole ), which sends the rotation energy to the electric generator located at the base of the structure . This generator uses some magnets and the properties of electromagnetic induction to produce an electrical voltage ( ie a difference in electric charge ) and therefore electric energy .
The wind makes the wind turbines work and the wind is converted into electricity . This method works best in windy areas, so for example in the North Sea or in the Baltic Sea . Furthermore, huge wind turbines are installed, not only on land but also at sea . You can really produce a lot of energy in this way . However, a disadvantage is that the wind does not blow constantly and therefore no constant amount of energy is produced . The wind energy is particularly clean because it releases little carbon dioxide .
The energy that is produced from biomass is called bioenergy . Biomass means animal and vegetable products that can be used for current production . Materials, for example, are wood scraps that are compressed, as are wheat, biodiesel and biogas . Biomass can be solid, liquid or gaseous .
The advantage is that the biomass can be versatile and can be transformed either into electric current or into heat or into fuel . The disadvantage is that unlike wind and solar energy, more carbon dioxide is released in the combustion of biomass .
To produce current from water, one must first accumulate a lot of water in the dikes . Afterwards the water can be let out, so as to make water wheels and turbines work in order to produce energy . Hydropower is used by man for energy production for a long time . Before the machines in the mills or sawmills were operated by water power, today they build several water plants, which for example use the current of a river . In the dams and artificial lakes large masses of water are stored which can also be used as drinking water at the same time . However, when stored, the oxygen content in the water drops and nature is strongly modified through the construction of large dams .