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GTD of electrical energy 1.2 syllabus

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What is Electricity – Generation, Transmission, Distribution, and
Utilization
Energy is required to perform many functions in day-to-day life. Energy exists in different forms in
nature, but the most important form of energy is electrical energy (or electricity). As we can experience,
electricity has become an integral part of our life because without electricity we cannot imagine our life.
Here,we will be clear about the concept of electricity, its generation, transmission, distribution, and
utilization.
What is Electricity?
Electricity is a form of energy that is a result of subatomic charged particles like electrons, protons, etc.
Electricity is one of the major inventions that changed human civilization. In today’s world, electricity is
used to perform several functions, and hence becomes a basic necessity of everyday life.
From elementary science, we know that all matter in this universe is composed of several atoms, and
each atom has a certain number of subatomic particles namely electrons, protons, and neutrons. Where,
electrons are the negatively charged particles, protons are the positively charged particles, and neutrons
are the charge-free or neutral particles.
But under ordinary conditions, each substance remains neutral, which means it has the same number of
protons and electrons. Electricity exists due to the charged particles (electrons and protons). These
charged particles can either be static or mobile. When particles are stationary and exhibit electricity, it is
known as static electricity. On the other hand, when the mobile charged particles exhibit electricity,
then it is known as current electricity.
As we discussed above, under normal conditions, the number of electrons and protons is the same in a
piece of material. But, when some electrons are removed from the material, then there is a deficit of
negative charge in it. Thus, the material becomes positively charged. On the other hand, if some
electrons are supplied to the material, then there is an excess of negative charge. Thus, the material
becomes negatively charged. In practice, electrons are removed from or supplied to the material
because protons are strongly bound in the nucleus of the atoms and hence cannot be detached easily.
In actual practice, the concentration of electrons in a material always tries to be uniform, i.e. the
material tries to be neutral as a whole. This is the only reason behind electricity. It can be understood by
considering an example in which two charged bodies have different electron concentrations and are
joined by a conducting wire. In this case, electrons move from the body with a higher electron
concentration to the body with a lower electron concentration. This movement of electrons will
continue until the electron concentration of both bodies becomes equal. This movement of electrons is
called electricity, more specifically the current electricity.
1.2) Generation, Transmission, Distribution, and Utilization
Generation of Electricity
The process of converting any form of energy into electricity is known generation of electricity. A system
of components that is used to generate electricity is called an electric power plant or power generating
station. At present, there are many ways of generating electricity, some important processes are
discussed below −
Electromechanical Process of Electricity Generation
In the electromechanical process of electricity generation, a conductor is moved in a magnetic field.
When the conductor cuts the magnetic field lines, electricity is produced in the conductor due to
electromagnetic induction. The device used for generating electricity in this method is known as a
generator. Depending on the nature of the electricity produced, the generator can be a DC generator or
an AC generator. This is one of the most extensively used methods for generating electricity in the world.
Electrochemical Process of Electricity Generation
In this method, chemical energy is converted into electricity. The most common example of this process
of electricity generation is the electricity produced by a cell or battery. In a battery, electricity is
generated due to chemical reactions. This process is used for small-scale electricity generation.
Solid-State Electricity Generation
It is a modern process of electricity generation. In this method, a semiconductor device like a
photovoltaic cell is used to convert light energy into electricity. When light beams of high intensity are
incident on a photovoltaic cell, a number of charge carriers (electrons and holes) are produced that
creates a potential difference. When an external circuit is connected to the photovoltaic cell, an electric
current starts to flow.
Miscellaneous Processes of Electricity Generation
There are several other processes available for the generation of electricity such as wind turbines,
biogas, biomass, geothermal, tidal, etc. Most of these are renewable sources of electricity.
Transmission of Electricity
After electricity gets generated at a power generating station, it gets stepped up, i.e., its voltage level is
increased, by a step-up transformer for transmitting over long distances. Though the generation of
electricity is practical and economical at low voltage, but its transmission is practical and economical at a
high voltage level.
The transmission of electricity is carried out with the help of transmission conductors (lines) supported
on the large steel towers. It is a usual practice to transmit electricity at a very high voltage either in the
form of AC or DC. In the case of AC transmission, the three-phase three-wire system of transmission is
used. The transmission lines are usually terminated at the receiving stations and substations.
Distribution and Utilization of Electricity
The distribution of electricity means supplying electricity to the end consumers for utilization. For this
purpose, several distribution substations are established at different locations in a city. These
distribution substations receive electricity at high voltages through transmission lines and reduce the
voltage level to a lower value. Now, this low-voltage electricity is then supplied to consumers through
distributors and feeders. The consumers use this electricity to power the electric loads like motors, fans,
light bulbs, etc.
Conclusion
Above, we discussed electricity, its generation, transmission, distribution, and utilization. As we
discussed above, electricity is a form of energy that is obtained from other forms of energy. Electricity is
generated by using a mechanism called a power plant. It is then transmitted through transmission lines
at a very higher voltage. Finally, it is stepped down to the desired voltage level and distributed to end
consumers for utilization, i.e., to power the electrical loads like motors, lamps, and other machinery.
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