Electricity Generation and Environmental Impact

This document discusses the generation of electricity and its impact on the environment. It covers the different methods of electricity production, such as hydro-power, solar-power, tidal power, wind-power, and geothermal power. It also explores the environmental effects of human activities like deforestation, farming, transportation, overfishing, and hunting/poaching of rare animals.

Running head: ELECTRICAL ENGINEERING
ELECTRICAL ENGINEERING
Name of the Student
Name of the University
Author Note

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Task 1:
The electricity is generated at the generating stations by high rated generators typically of the
range of megawatts. The energy is generated by either using renewable resources like wind,
water, solar or nuclear and/or non-renewable resources like coal, natural gas etc. The
generated power is transmitted through step up transformers for pushing the power in the
long distances. The electrical current is transmitted from the transformers to the substations
via high voltage transmission lines. The substations have step down transformers which
lowers the voltages so that it can be sent to small power requirement lines. Then the power
goes to the pillar boxes in the locality via distribution lines where step down transformer is
installed which further steps down the voltage into the level of home usage (Grigsby 2018).
The pillar boxes are often identified as big green boxes mounted on the poles or may be
sitting on the ground. These particular transformers are known as the pad mount
transformers. Then the power goes to the meter boxes installed in the houses where a large
Fuse is installing for breaking the circuit in case of over-current conditions. From the meter
box the power goes to individual switch-boards or service panels and there also fuses are
installed for protecting devices from high current. Finally, the switches those are installed in
the switchboard supplies power to the devices (like fan, tubes) when turned on.

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Figure: Generation of electricity, distribution and transmission
Now, power is lost in transmission from national grid to houses because of the heating effect.
To reduce this heating effect the generated power is raised to very high voltage before
transmission. In this way as power remains constant the current is significantly reduced and
thus very low loss of power through heating effect which is mathematically known as I 2 R
loss. This method of loss reduction is very effective in power stations and mostly followed by
power distribution companies.
Task 2:
Name of the human activity Impact on the environment
Deforestation Deforestation has several impacts on the
environment that includes loss of habitats
for the plants, insects and animals,
increment of greenhouse gases in the
environment, soil erosion and flooding due
to less water content in the air, homeland

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destruction.
Farming The farming or agriculture creates many
environmental issues that are related with
the climate change, genetic engineering,
pollutants, soil degradation and waste
(Goudie 2018). The liquid biofuels
produced from the agricultural waste emits
pollutants that are toxic to environment and
contributes towards oxidizing smog.
Transportation Transports are the major users for energy as
this burns most of the petroleum of world.
Thus it creates air pollution by emission of
carbon-di-oxide, nitrous oxides and thus one
of the most significant contributor towards
global warming.
Overfishing Overfishing has significant effect on the
environment as this adversely affect the
marine biodiversity which is the interaction
of species in the marine ecosystem (Goudie
2018). Overfishing hampers the food chain
and this in turn kills many sea mammals,
sharks and sea birds although they are not
hunted by humans.
Hunting/poaching of rare animals Hunting directly affects the environment as
it hampers the natural predation and growth

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of population. Excessive hunting endangers
the wildlife and the environment as every
animal in environment contributes
significantly in the ecosystem. Hunting of
endangered species or often known as
poaching can permanently extinct the
species.
Task 3:
a) Electricity that are produced can be of two forms, namely Alternating current (AC) and
direct current (DC).
Alternating current production method by generator:
The AC generator basically produces alternating potential difference which is in turn
generates AC current when connected with a load or conductor. The produced potential
difference is approximately sinusoidal in nature and varies between the frequency-range from
48 to 52 Hz (50 Hz on average). An AC generator has a coil of wire which is rotating inside a
magnetic field. When a particular side of coil is passed through the magnetic field a potential
is induced in that side of the coil and thus creates a potential difference between two sides of
the coil. Now, with the rotation the induced side of the coil moves downward and thus
reverses the induced potential. Hence, the potential difference between two sides also
reverses (Guarnieri 2018). Thus when a conductor is attached between the two sides of the
coil an alternating current is produced. The output voltage or potential difference of the AC
generator or alternator is often represented in a time scale where potential difference is taken
in the Y axis and time in the X axis. The induced voltage in the coil is given by Faraday’s law

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E = N*(dϕ/dt). Here, N= number of turns in coil and ϕ = magnetic flux. Thus the induced
voltage or the magnitude or AC current produced by alternator can be increased by increasing
the number of turns in coil and increasing the strength of magnetic field. Another way of
increasing the rate of change of magnetic flux is to increase the rotation speed and thus it
increases the magnitude of alternating current.
Figure: Schematic diagram of Alternator and its operation
Direct current production method by battery:
A battery whether dry cell or wet cell has three primary components namely anode, cathode
and the electrolyte. The cathode is the positively charged side and Anode is the negatively
charged side and when they are joined by a conductor a current can flow from cathode to
anode. The ionization of electrolyte produces many cat-ions and anions inside the cell. The
cat-ions have many free electrons which they deposit in the cathode when they reach there by
the laws of ionic attraction. Anode is lot of free electrons and emits in the electrolyte for

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neutralizing positively charged ions. However, the electrolyte keeps the free electrons to
directly go to the cathode from anode within the cell. Only way the electrons can reach to
cathode when a conductor is joined between them from outside the battery cell. Thus charge
or current flow in the opposite direction of electron flow i.e. from cathode to anode. Now, as
the rate of electro-chemical process inside the battery happens in a constant rate ad current
flow is unidirectional, hence this current is known as Direct current having a constant
magnitude (Chen et al. 2017). Now, batteries can only deliver DC current for a limited
amount of time. Some special batteries known as rechargeable batteries can deliver power
again and again after recharge. Recharging is a process where the flow of electrons are
reversed by applying external power source. Hence, the electrochemical process is reversed
and cathode and anode returns in their original states after recharging is complete.
Figure: schematic of battery and its operation
b) Electricity can be generated in many renewable ways like hydro-power, solar-power, tidal
power, wind-power and geothermal power. The most common and efficient way to generate

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electricity is hydro-power as many rivers are available where hydro-turbines can be easily
installed. The hydro-power plant is a combination of large hydro-turbines which capture the
kinetic energy of falling or flowing water and converts it into mechanical energy. The
mechanical energy is then converted back to electrical energy by using generators. The main
parts of a hydroelectric plant consists of a Dam, turbine, generator and transmission lines.
The Dam controls the water flow and raise the level of water to increase the energy input by
creating falling water. The falling water forces the turbine blades to rotate. The design of the
turbine blades are very important for most efficient power generation. The design varies
based on water level and initial flow velocity of water. The turbine is connected with a
generator through a shaft and gears to increase the speed of rotation and the generator
converts the mechanical input energy to electrical energy. Transmission lines are connected
to the output terminals the generators set which transmit power to the substation or directly to
home consumers depending on amount of power generated (Jawahar and Michael 2017). The
amount of electricity generated by a hydroelectric plant depends on the falling height of the
water and the amount of water which is falling. The height of falling water depends on the
height of the dam and hence more the height more is the energy generated by hydro-plant.
The water available to the turbine depends on the amount of water that is flowing thorough
the river, which means big rivers will have big amount of flowing water. Thus production of
more electricity requires hydro-electric plants installed in wide rivers having high rate of flow
of water. The power produced by a dam is given by the following formula
P= h∗Rf ∗η
11.8
P = power generated in KW
h = height of the dam in feets.
Rf = water flow of river in ft^3/sec.

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η=% eficiency(typically in the range 60% to 90%)
The electrical energy produced in a year is given by P*24 hours *365 days. Thus
hydroelectric power plants can produce sufficient amount of energy in a large river with very
high rate of flow of current.

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References:
Chen, Y., Fu, K., Zhu, S., Luo, W., Wang, Y., Li, Y., Hitz, E., Yao, Y., Dai, J., Wan, J. and
Danner, V.A., 2016. Reduced graphene oxide films with ultrahigh conductivity as Li-ion
battery current collectors. Nano letters, 16(6), pp.3616-3623.
Goudie, A.S., 2018. Human impact on the natural environment. John Wiley & Sons.
Grigsby, L.L., 2018. Electric power generation, transmission, and distribution. CRC press.
Guarnieri, M., 2018. The Development of ac Rotary Machines [Historical]. IEEE Industrial
Electronics Magazine, 12(4), pp.28-32.
Jawahar, C.P. and Michael, P.A., 2017. A review on turbines for micro hydro power plant.
Renewable and Sustainable Energy Reviews, 72, pp.882-887.