Ecology

# How is electricity generated

Naturally, electricity has always been present among us. So much so that primitive man could distinguish electricity in lightning. Electricity is a form of energy that is present in most of the activities of the human being. In an increasingly developed society, we depend more and more on it. Even for those more everyday activities, such as brushing our teeth with an electric toothbrush, we need to be supplied with electricity. From its use, after all, essential activities are derived.

What is electricity

Electrical energy is the potential result between two or more points with different electrical charges . In this way, an electric current is established between the same points through an electric conductor. Academically, electricity was not studied until the seventeenth and eighteenth centuries, and it was not until the nineteenth century that this source of energy began to be used for industrial and domestic activities.

To measure electricity we do it with units of electrical power. The measurements we use the most today are the kilowatt hour (kWh), the megawatt (mW), the milliwatt (mW) or the microwatt (μW). For example, the electricity and gas bills that indicate the consumption of the house, do so according to the kilowatts spent per hour. Another fact is that electricity is accumulative , that is, its chemical content can be stored and then used. This is what cells or batteries do, for example.

How electricity is produced

If you have ever wondered how electrical energy is generated, in this section we will clarify it for you. There are two different ways to produce electrical energy. On the one hand, we can talk about the electrical energy that is created in power plants. This is possible from other primary energies . That is, electricity is created from other energies such as wind, thermal or hydraulic . Even so, the one we use the most is mechanical energy. Another way to produce electricity is in small quantities with specialized devices.

Focusing on mechanical energy, in order for electrical energy to be produced, the plants put into operation turbines connected to generators . These turbines can be moved by steam that is produced by heating the water, by nuclear reactions or by the burning of fossil fuels. In this way, the movement is transformed into electricity.

Types of power plants

Depending on the primary energy source used to produce mechanical energy, one classification or another of power plants can be made. From this distinction, we find 8 types of power plants where electricity is produced:

• Hydroelectric plants : the water coming from a natural or artificial stream and, stored in reservoirs, is dropped from a great height. The unevenness and the impact of the falling water acts on the blades of a hydraulic turbine that sets it in motion.
• Conventional thermal power plants : are those that use fossil fuels such as coal, gas or fuel oil. These are burned in a boiler and thus heat energy is generated that is used to obtain water vapor. This high pressure steam will drive the blades of a steam turbine.
• Combined cycle power plants : in these power plants, the thermal energy of natural gas is transformed into electricity thanks to the joint work of two turbines: one gas and the other steam. Natural gas is first burned to drive the gas turbine and then the residual heat from the gases is used to produce steam and drive a steam turbine.
• Nuclear power plants : a large amount of energy is obtained by the fission of uranium atoms, this energy is used to obtain water vapor, which will be used to move a turbine that, thanks to the alternator, will produce electricity. To know the Nuclear Power Plants in Spain: number and where they are , you can read the following article.
• Wind power plants : wind power plants take advantage of the wind. The kinetic energy of the wind moves the blades of a wind turbine which in turn operates a turbine that will convert this energy into electrical energy.
• Solar power plants: there are two types of solar power plants, the thermosolar ones that heat water with the sun’s heat to generate steam that moves a turbine; or photovoltaic power plants, which, thanks to photovoltaic cells, directly transform solar energy into electrical energy. You can learn more about What is solar energy here.
• Central tidal : These plants use the rise and fall of tides to power a turbine through a generator to produce electricity.
• Biomass or solid urban waste (MSW) plants : they follow the same operation as a conventional thermal power plant with the only difference that the fuel used in the boiler comes from solid urban waste. If you would like to discover more about Biomass energy: advantages and disadvantages , click on the article.

Surely more than once you have wondered how electricity reaches your home once it has been generated. We bring you the answer to this question and we explain it to you step by step:

1. At the moment in which the electrical energy is obtained, it is directed by transmission lines , elevated or underground, from the power plants where the electricity is produced to the electrical substations.
2. Once in electrical substations , normally located outdoors or on the outskirts of cities but always close to generating plants, the voltage, frequency, number of phases and connections of two or more circuits are appropriately transformed.
3. Once it is transformed, the energy is sent back through the transmission lines to the homes .
4. Thanks to the cables that are piped into the walls, floors or ceilings of our houses, we can receive electricity.