Power plants allow the generation of electrical energy on a large scale.
The generation of electrical energy is the process that makes possible the transformation of some type of primary energy into electrical energy . The procedure is carried out using a device known as an electrical generator .
To understand the concept of electrical energy , you must first pay attention to several terms. The first thing to consider is that energy , in the field of physics , is the capacity of a system to carry out work. Many times this capacity is associated with a natural resource.
When said energy found in nature is capable of being transformed into a different energy, it is classified as primary energy . Wind energy (from the wind) and solar energy (from the sun) are examples of primary energies.
Returning to the idea of electrical energy, it is a type of energy that is produced thanks to the movement that electrons (elementary particles that have a negative charge) make between two points when there is a potential difference .
Electrical energy generation and potential difference
Electric potential is the work necessary for an electric charge to move between two points. The difference in potential that is registered between the points is called tension or voltage .
To achieve the generation of electrical energy, an appliance is used that can preserve the potential difference between two points (which, in this context, are mentioned as terminals , terminals or poles ). This element is called an electrical generator .
Generators are rotating machines that present relative movement thanks to the use of an energy source that can be non-renewable (such as oil or coal) or renewable (wind, sun). By rotating between a magnetic field and an electrical conductor, they produce electric current : that is, a flow of electric charge. What a generator does, in short, is convert mechanical energy into electrical energy.
The current produced by the electric generator is an alternating current since the direction and magnitude vary cyclically. With a rectifier , alternating current can be transformed into direct current , whose direction does not change. This is key since electronic devices usually operate on direct current.
The power plants
Power plants are industrial facilities that are dedicated to the generation of electrical energy on a large scale. These plants can have several generators.
If the power plant uses thermal energy to generate electrical energy, it is called a thermoelectric plant . The thermal energy in question can come from the combustion of fossil fuels or the controlled fission of uranium. In the first case, we are talking about conventional cycle plants , while in the other we are talking about nuclear plants .
It is important to indicate that, when producing electrical energy, power plants generate residual heat . In order to reject said heat, cooling towers or cooling towers are used that use the evaporation of water for this purpose.
The transmission network and the distribution network make up the electrical network .
From electricity generation to home consumption
From the moment the generation of electrical energy is completed in a power plant until a person can use electricity in their home, a series of successive stages are completed. Even steps prior to the generation itself can be recognized, such as the extraction of oil , coal or natural gas in some cases.
Through conductors installed in electrical towers or underground roads that form the transportation network, the electrical energy generated at the plant is sent to a substation . In these facilities there are transformers that, while conserving power , are dedicated to reducing or increasing the voltage and thus guarantee the appropriate level so that the electrical energy is transmitted and distributed to the homes.
There are usually substations located near the power plants that are responsible for increasing the voltage level of the electrical energy sent through the transportation network . Other substations, on the other hand, reduce the voltage to deliver power to the distribution network .
Through this distribution network, electrical energy reaches homes and, thus, to the end user. It can be said, then, that the electricity that allows a person to illuminate a room, cook with an electric oven or turn on a computer or television comes from the distribution network.
Although the electricity rate paid by the user has various components, the invoices are sent and collected by the marketing company. This company receives the reading of the electric meter installed by the distributor to record consumption. In some regions, however, the distribution and marketing of electrical energy is carried out by the same firm.
From the moment the generation of electrical energy takes place until the consumption of electricity in the home arrives, various phases are gone through.
The environmental impact
It is important to consider that the generation of electrical energy, as well as transmission , distribution and consumption , generate an environmental impact . Power plants, for example, consume natural resources for their power and generate greenhouse gas emissions when they operate. They also use water that is used for cooling .
When powered by fossil energy, plants emit waste in the form of ash. Nuclear power plants, for their part, generate radioactive waste that is extremely dangerous due to its contaminating potential.
For the installation of electrical energy transmission lines, in turn, it is necessary to eliminate vegetation . The towers also usually cause the electrocution of thousands of birds each year.
Electrical energy, therefore, favors climate change , threatens the ozone layer and contributes to acid rain and smog. Of course, beyond these negative effects that must be controlled and reduced if possible to seek sustainability , this type of energy is essential for modern life .
The analysis of the energy balance , which reflects the balance or imbalance in the flow of energy from generation to consumption, is important for the regulation of the electricity sector and the development of an energy policy that takes into account the needs of society. The State, through subsidies, tax incentives and other resources, can encourage research and development activities and promote technological innovation to enhance energy efficiency and promote practices that are less harmful to the environment.