Thermal energy năng lượng nhiệt

HO CHI MINH CITY UNIVERSITY OF
TECHNICAL EDUCATION


Report:

RENEWABLE
ENERGY
(Subject: ENGLISH FOR THERMAL ENGINEERING)

Instrustor: Ph.D ThanhTrung Dang
Group: 4
HO CHI MINH CITY –23/11/2015


FULL NAME:

STUDENT ID:

1. MAI HOÀNG BẢO

- MSSV 13147003

2. NGUYỄN TRANG DOANH

- MSSV 13147008

3. TRẦN QUỐC HUY

- MSSV 13147024

4. NGUYỄN VĂN KỲ

- MSSV 13147029

5. NGUYỄN VIẾT LÂM

- MSSV 13147031

Instrustor: Ph.D ThanhTrung Dang

SCORE:
TEACHER’S FEEDBACK:

TEACHER’S SIGNATURE


RENEWABLE ENERGY

APPENDIX

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RENEWABLE ENERGY
I.

INTRODUCTION
Energy with climate change issues are becoming a major concern of
humanity, including the energy issue has become an important
issue, which is particularly interested on the world, due to the global

energy crisis, the non-renewable energy sources such as coal, oil
and natural gas which have become depleted and scarce, while
energy wastage have already warned in many countries.
Therefore, finding renewable energy sources is necessary. Along
with the development of science and technology, scientists have
discovered the energy sources which come from energy resources
are not exhausted when used or not have to recycle in the short
time, non-polluting and can be used for the long time such as:
hydroelectric, wind, solar radiation, geothermal energy, bio energy
and so on.
In our report, we just mention four renewable which is popular on
the world.

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RENEWABLE ENERGY

II.

SOLAR ENERGY
1.

Introduction

Solar energy is becoming a popular energy source due to the fact that it is the
most abundant and most cost effective energy source on the planet. Put
simply, solar energy is energy derived from the sun, and this energy is not
only clean, but renewable and costs nothing. Solar energy is created when the
power of the sun is harnessed in order to produce energy. It is said that the

amount of energy that the Sun provides to the Earth in a single day can power
the entire planet and all of its energy needs for a whole year. Because solar
energy is available as long as the Sun is available, it is also considered a
renewable source of energy. It is a clean source of energy as well, due to the
fact that it does not produce byproducts or pollutants that will harm the
environment.
Solar energy was in fact the first source of energy used by humans. It was
initially used to dry clothing or items, or to heat through direct contact.
However, since the 1950’s, solar energy is used to create sources of power to
fuel technology, homes, and many businesses. Given that technology is
evolving at the speed of light, solar energy is becoming more proficient as an
energy source, and is recognized as a feasible alternative to fossil fuels.
2.

Classified
2.1.

Passive Solar Energy

Passive solar energy is precisely what it sounds like. Panels and solar cells
are not used, but rather, structures or buildings will be constructed in a way
to capture the sun’s power through the use of windows or tanks. These
systems will then heat homes or water, but cannot be converted into actual
electricity.

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RENEWABLE ENERGY
2.2.

Active solar energy

Active solar energy is just the opposite. Solar Panels or solar cells will be
used to capture the sun’s energy. The panels or cells are placed in a way
that they will maximize the sun’s exposure. The sun’s energy is then
converted into direct or alternate current electricity which is then stored into
batteries. In some cases, the electricity will be fed into a grid system of a
utility plant when larger amounts of energy are needed. The power of the
sun is being utilized everywhere today. Solar energy is used to create
sources of power to fuel technology, homes, and many businesses.

3.

Applications
•

•

•

Concentrating Solar Power (CSP): Concentrating solar power (CSP)
plants are utility-scale generators that produce electricity using mirrors
or lenses to efficiently concentrate the sun’s energy. The four principal
CSP technologies are parabolic troughs, dish-Stirling engine systems,
central receivers, and concentrating photovoltaic systems (CPV).
Solar Thermal Electric Power Plants: Solar thermal energy involves
harnessing solar power for practical applications from solar heating to
electrical power generation. Solar thermal collectors, such as solar hot
water panels, are commonly used to generate solar hot water for

domestic and light industrial applications. This energy system is also
used in architecture and building design to control heating and
ventilation in both active solar and passive solar designs.
Photovoltaics: Photovoltaic or PV technology employs solar cells or
solar photovoltaic arrays to convert energy from the sun into
electricity. Solar cells produce direct current electricity from the sun’s
rays, which can be used to power equipment or to recharge batteries.
Many pocket calculators incorporate a single solar cell, but for larger
applications, cells are generally grouped together to form PV modules
that are in turn arranged in solar arrays. Solar arrays can be used to
power orbiting satellites and other spacecraft, and in remote areas as a
source of power for roadside emergency telephones, remote sensing,
and cathodic protection of pipelines.

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RENEWABLE ENERGY
•

•

•

4.

Solar Lighting: Also known as daylighting, this is the use of natural
light to provide illumination to offset energy use in electric lighting
systems and reduce the cooling load on HVAC systems. Daylighting
features include building orientation, window orientation, exterior

shading, saw tooth roofs, clerestory windows, light shelves, skylights,
and light tubes. Architectural trends increasingly recognize daylighting
as a cornerstone of sustainable design.
Solar Cars: A solar car is an electric vehicle powered by energy
obtained from solar panels on the surface of the car which convert the
sun’s energy directly into electrical energy. Solar cars are not currently
a practical form of transportation. Although they can operate for
limited distances without sun, the solar cells are generally very fragile.
Development teams have focused their efforts on optimizing the
efficiency of the vehicle, but many have only enough room for one or
two people.
Solar Power Satellite: A solar power satellite (SPS) is a proposed
satellite built in high Earth orbit that uses microwave power
transmission to beam solar power to a very large antenna on Earth
where it can be used in place of conventional power sources. The
advantage of placing the solar collectors in space is the unobstructed
view of the sun, unaffected by the day/night cycle, weather, or seasons.
However, the costs of construction are very high, and SPSs will not be
able to compete with conventional sources unless low launch costs can
be achieved or unless a space-based manufacturing industry develops
and they can be built in orbit from off-earth materials.

Advantages and disadvantages of solar energy
4.1.
•
•

•

Advantages

Solar energy is free although there is a cost in investment, operation,
and maintenance.
Solar energy does not cause pollution. However, solar collectors and
their other associated equipments are manufactured in factories that
cause some pollution.
Solar energy can be used in remote areas where it is so expensive to
extend the electricity power grid.

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RENEWABLE ENERGY
•
•

4.2.
•

•

•
•

III.

Many small devices such as calculators and other low power
consuming items can be powered by solar energy effectively.
It is estimated that fossil energy on the world will last for 30 to 40
years. On the other hand, solar energy is infinite or forever.

Disadvantages
The initial cost is the main disadvantage of installing a solar energy
system. The cost of the semi-conducting materials is still high. So, the
cost of solar energy is also high comparing with non-renewable energy
to generate electricity. As energy shortage is in serious statement, solar
energy is becoming more price-competitive.
Solar panels require a large area for installation to achieve high
efficiency. The efficiency of the system also relies on the location of
the sun although this problem can be overcome with the installation of
certain components.
The production of solar energy is influenced by the state of clouds or
the pollution in the air.
Similarly, no solar energy will be produced during nighttime although
a battery backup system will solve this problem.

WIND POWER
1.

Introduction

Wind power is the conversion of the energy in wind into a more useful form
of energy, like electricity. It is a renewable source of energy that helps to cut
down on the pollution of earth's air. Wind energy is extracted from air
flow using wind turbines or sails to produce mechanical or electrical
energy. Windmills are used for their mechanical power, wind pumps for water
pumping, and sails to propel ships. Wind power as an alternative to fossil
fuels, is plentiful, renewable, widely distributed, clean, produces
no greenhouse gas emissions during operation, and uses little land. The
net effects on the environment are far less problematic than those of
nonrenewable power sources.

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RENEWABLE ENERGY
Wind farms consist of many individual wind turbines which are connected to
the electric power transmission network. Onshore wind is an inexpensive
source of electricity, competitive with or in many places cheaper than coal or
gas plants. Offshore wind is steadier and stronger than on land, and offshore
farms have less visual impact, but construction and maintenance costs are
considerably higher. Small onshore wind farms can feed some energy into the
grid or provide electricity to isolated off-grid locations.

2.

TURBINE DESIGN

Wind turbines are devices that convert the wind's kinetic energy into
electrical power. The result of over a millennium of windmill development
and modern engineering, today's wind turbines are manufactured in a wide
range of horizontal axis and vertical axis types. The smallest turbines are used
for applications such as battery charging for auxiliary power. Slightly larger
turbines can be used for making small contributions to a domestic power
supply while selling unused power back to the utility supplier via
the electrical grid. Arrays of large turbines, known as wind farms, have
become an increasingly important source of renewable energy and are used in
many countries as part of a strategy to reduce their reliance on fossil fuels.
Wind turbine design is the process of defining the form and specifications of
a wind turbine to extract energy from the wind. A wind turbine installation
consists of the necessary systems needed to capture the wind's energy, point

the turbine into the wind, convert mechanical rotation into electrical power,
and other systems to start, stop, and control the turbine.

3.

Principle of operation of wind energy

The working principle of wind turbine is very simple. A wind turbine works
in opposite state with an electric fan. Instead of using electricity to generate
air, the wind turbine uses air energy to generate electricity. Wind energy
effects blades which are connected to the rotor axis. The rotor will rotate the
generator shaft to produce electricity.

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RENEWABLE ENERGY
Wind turbines are placed high on the head to get most wind energy. At an
altitude of 30 meters above the ground, the wind turbine can get higher air
velocity, it gets faster rotor speed. Wind turbines can be connected to an
electricity network to supply for a national power.

4.

APLLICATIONS

Wind is one of those resources we find all around us in nature. It’s one of the
more environmental-friendly alternative energies around and has been tapped
into for thousands of year. It has a wide variety of uses.
•

•

•

Energy-generating wind turbines: wind turbines are installed to capture the
power of the wind and be able to convert it to energy. This can be on a
broad scale, such as the wind turbines found on wind farms or can be on a
smaller scale, such as individual wind turbines people use to generate
power to their home.
Wind-powered water pumps: using the wind to help pump water out of the
ground is not something new. It is however a very helpful and sometimes
much needed tool when it comes to come communities and countries.
Tapping into the power of the wind makes sense, especially when it comes
to the work needed to pump water.
Wind-powered sports: for many, many years the wind has been used to
power our sports, both literally and figuratively. Everything from simple
kite-flying to sailing, wind-surfing, hang-gilding, para-sailing, wind-skiing
and more.

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RENEWABLE ENERGY
5.

Advantages and disadvantages of wind energy:
5.1. Advantages
-

Wind Power Stations have the advantage over Fossil Fuel Power
Stations as they do not produce any greenhouse gases such as carbon
dioxide or water vapor. They also do not produce gases that help
make acid rain such as sulfur dioxide.

-

Wind energy is the source generated by the wind, so it is a clean energy.
Wind energy does not pollute the air compared to the thermal power
plants based on burning coal or gas fuel.

-

Wind energy is available in many areas of a nation. Thus, the supply of
wind energy is very rich country.

-

Wind power is a form of renewable energy that the price is low by
advancing science today.

-

Wind turbine can be built on the farm, so it is suitable for rural areas.

5.2. Disadvantages
-

Wind turbines have to be carefully placed. They must be in positions
where there is a constant, steady supply of wind. In fact, the wind must

not become too strong or it may damage the turbine. Also, huge numbers
of electricity pylons are built on land to carry the electricity to the
electric company. These pylons in areas of natural beauty are a major
reason for local people to object to wind farms and their consequences.

-

Wind power must compete with conventional sources at a basic price.

-

The initial investment for a wind turbine is still high.

-

Wind energy is an intermittent energy source, and it has to combine with
another power when needed.

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RENEWABLE ENERGY
-

The locations usually have strong wind are far away from city. However,
the demand for using electricity of these places is not more than town.

Nuclear energy

IV.

1.

Introduction

Nuclear energy is energy that is generated through the use of Uranium, a
natural metal that is mined all over the world. Nuclear energy is created
through complex processes in nuclear power stations, and the first nuclear
power station was established in 1956 in Cumbria, England. Today, many
military operations and vessels use nuclear power plants and nuclear energy
for their energy source, and nuclear energy is used in many other capabilities
such that it provides 16% of the Earth’s energy requirements.
.
2.

Classified

Currently, there are two ways to produce nuclear energy, through the use of
fission and fusion. Fission reactions are more easily controlled than fusion
reactions. This is why all nuclear power plants use fission reactions to
produce energy and electricity.

2.1. Nuclear Fission
In nuclear power plants, the most widely used method to produce energy is
through the use of fission. The idea of fission is to split atoms, usually
uranium, in a nuclear reactor. When an atom splits, neutrons are released,
the neutrons then strike other atoms and begin a chain reaction. The
splitting of the atoms produces great amounts of energy, and that energy
turns water into steam, which drives turbines. The turbines spin a generator

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RENEWABLE ENERGY
and produce electricity, which is harnessed.

2.2. Nuclear fusion
Nuclear fusion is another method of producing energy. The sun uses this
process to produce its energy. As of 2009, nuclear fusion has not yet been
controlled by man and is not used as a means of producing electricity. Its
primary use is still only in the production of nuclear weapons. Nuclear
fusion works on the idea of forcing two nuclei together through intense
pressure. When the two nuclei fuse, a new element is formed, and a large
amount of energy is released. This process also sets off a chain reaction,
which is difficult to control.
3.

Nuclear power plant

A nuclear power plant is a facility for the production of electricity
using nuclear energy.
Its operation is similar to a thermic power plant. The difference is
that the power source from a nuclear plant is nuclear fission of
certain atoms while in a thermic power plant the heat source (thermal
energy) from burning of one or more fossil fuels (coal, natural gas ,
fuel ..). As in a conventional thermal power plant the heat is used to
generate steam that drives a steam turbine connected to a generator
that produces electricity.

The thermal energy that nuclear power uses to generate electricity is

generated by a nuclear reactor. Within the nuclear reactor fission
reactions in chain occur in controlled way. The element to fission is
natural uranium or enriched uranium. Enriched uranium is
natural uranium with a proportion of the isotope uranium-235 higher.
In addition to the reactor, a nuclear power plant always consists of a
steam turbine, an alternator, two or three -primary, secondary, and
tertiary- circuits and one or more cooling towers condenser fluid,
usually water. The overall efficiency is between 30% and 40%.

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RENEWABLE ENERGY
It is usually considered the operating lifetime of a nuclear power
plant in about thirty years. The main problem is that no one knows
what to do with nuclear waste they generate

3.1. Basic of operation of nuclear power plant
In a nuclear power plant, energy is extracted from the nucleus
of atoms through its division (nuclear fission) since breaking
release the binding energy within the atom linking the particulates.
Nuclear fission is caused by artificial and controlled manner. In
this, a large atom of a chemical element fires a neutron, a small
particle at a certain speed, which breaks the atom (breaking its
core, formed by neutrons and protons linked together by highly
energetic links) in an exothermic nuclear reaction, it means energy
is released as heat (thermal energy).

To achieve that energy obtained be greater than the energy used, it
is necessary that nuclear reactions be chain reactions. Thus,

although much energy is needed to start the nuclear chain reaction,
once the reaction is initiated not much energy is required to
maintain it, and there comes a time in which the energy obtained is
higher than the energy used. To achieve this it is necessary that the
largest chemical element (called heavy, with a high atomic mass)
be also radioactive. The element used often is a rare
isotope of uranium.

This is done in the nuclear reactor, where also they pose tubes with
a fluid called refrigerant, which is responsible for transporting the
heat (thermal energy) extracted from the uranium from the
reservoir, cooling it. This thermal energy is used to heat water to
boiling, and water vapor pressure is used to move the blades of a
turbine, thus we have transformed the thermal energy to

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RENEWABLE ENERGY
mechanical energy. Then, the electric generator (or alternator)
converts this mechanical energy to electrical energy.

This process is explained in more detail in the section: operation of
a nuclear power plant .

4.

Applications

4.1. Water desalination

Readily available drinking water is out of reach for as much as a fifth of the
world’s population, a bar to human development. One solution is water
desalination, which extracts salt from seawater to produce drinkable fresh
water. Nuclear energy is being used for some desalination efforts, but the
potential in this arena is enormous and has multiple benefits over the more
common fossil-fuel based desalination.

4.2. Scientific research
Researchers in nearly all fields of science use radioisotopes in their work.
The U.S. Food and Drug Administration requires all new drugs to be tested
for safety and effectiveness. More than 80 percent of those drugs are tested
with radioisotopes.
Radioisotopes also are essential to the biomedical research that seeks causes
and cures for diseases such as AIDS, cancer and Alzheimer’s disease.
Researchers also use radioisotopes in metabolic studies, genetic engineering
and environmental protection studies
Carbon-14, a naturally occurring, long-lived radioactive substance, allows
archaeologists to determine when artifacts containing plant or animal
material were alive, created or used.

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RENEWABLE ENERGY
4.3. Use in agriculture
Technical advancement in nuclear technology has helped in the production
of crops seed having more crop production and safe from insects and other
illness.
Nuclear radiations helps to preserve fruit and vegetable for a longer time.
This also helps in analyzing soil type and gives information to enhance its

quality.

4.4. production of electric power
Production of nuclear power is similar to other plants with the difference
that nuclear energy is used for the production of that rotates the turbine
blades with its exhaust.

4.5. Atomic bomb
The bomb producing shock waves and heat and radiations due to fission.
The energy produced is malisons time greater the conventional TNT
weapon.
The atomic bomb has been used only twice in warfare. The first was at
Hiroshima in 1945. In an instant, 66,000 people were killed and 69,000
injured by a 10-kiloton atomic explosion.
On August 9, 1945, Nagasaki fell to the same treatment with a Plutonium
bomb. Its targeted nearly half of the city. In few seconds, Nagasaki's
population dropped from 422,000 to 383. Over 25,000 people were injured.
5.

Advantages and disadvantages of nuclear energy
5.1. Advantages
-

Nuclear power is a highly reliable energy resource as good as other
fossil fuel energy resources such as coal, gas, etc. Except several
dangerous cases, nuclear power plants operate reliably for the whole
day without any changes.

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RENEWABLE ENERGY
-

Large amounts of nuclear energy can be produced from the fission on
radioactive elements such as Uranium. The cost of nuclear fuel is very
low to compare with other energy sources such as coal and gas.
Currently, Uranium prices are also quite low to making nuclear
electricity price lower.

-

The electricity produced from Nuclear Power is quite low at around 35c/ kWh making its attraction to compare with others such as hydro
power plant. Nuclear plants also have long life( 40-60 years ).

-

No greenhouse gas (GHG) emission or air pollution: Nuclear electricity
does not produce any GHG emissions or cause air pollution from the
combustion of fossil fuels unlike coal, oil, or gas. This makes them
more attractively by its cheapness and non-carbon dioxide producing
electricity.

-

High load factor: Nuclear power plants have very high load factors in
excess of 80%. They can generate power almost 24/7 and only require
shutdown for periodic maintenance.

-

Huge potential: Nuclear energy potential is almost infinite comparing
with the limited and peak features of other forms of energy such as
wind, geothermal energy, oil, gas and others .

5.2. Disadvantages

V.

-

Nuclear power generates radiation, which can be harmful or fatal to
infect people.

-

A nuclear meltdown can often occur which will release massive
amounts of radiation into the environment.

-

Radioactive nuclear waste is produced by nuclear power plants. This
waste cannot be just thrown out.

-

There are international dangers. Some reactors produce plutonium
which can be used to make nuclear weapons.

GEOTHERMAL ENERGY

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RENEWABLE ENERGY

1.

Introduction

Geothermal energy is a renewable form of energy originating in the heat that
is naturally present in the deepest layers of the Earth (the average geothermal
gradient in the Earth’s crust is approximately 3 0C of every 100 meters towards
the centre). This energy resource can be exploited by drilling deep wells and
conveying the hot fluids (water and/or steam) trapped in the subsoil to the
surface. Geothermal plants convert the heat of these “geo fluids” into
electrical energy, which can be combined with the production of heat for
urban heating and various other “direct” uses, such as in greenhouse
cultivation or in thermal spas.

2.

Types of geothermal power plants

All geothermal power plants use steam to turn large turbines, which run
electrical generators. In the Geysers Geothermal area, dry steam from below
ground is used directly in the steam turbines. In other areas of the state, superhot water is "flashed" into steam within the power plant, and that steam turns
the turbine.

2.1. Direct dry steam
Steam plants use hydrothermal fluids that are primarily steam. The steam

goes directly to a turbine, which drives a generator that produces electricity.
The steam eliminates the need to burn fossil fuels to run the turbine. (Also
eliminating the need to transport and store fuels!).
This is the oldest type of geothermal power plant. It was first used at
Lardarello in Italy in 1904. Steam technology is used today at The Geysers
in northern California, the world's largest single source of geothermal
electricity. These plants emit only excess steam and very minor amounts of
gases.

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RENEWABLE ENERGY
2.2. Flash and double flash cycle
Hydrothermal fluids above 360°F (182°C) can be used in flash plants to
make electricity.
Fluid is sprayed into a tank held at a much lower pressure than the fluid,
causing some of the fluid to rapidly vaporize, or "flash." The vapor then
drives a turbine, which drives a generator.
If any liquid remains in the tank, it can be flashed again in a second tank
(double flash) to extract even more energy.

2.3. Binary cycle
Most geothermal areas contain moderate-temperature water (below 400°F).
Energy is extracted from these fluids in binary-cycle power plants.
Hot geothermal fluid and a secondary (hence, "binary") fluid with a much
lower boiling point than water pass through a heat exchanger. Heat from the
geothermal fluid causes the secondary fluid to flash to vapor, which then
drives the turbines.
Because this is a closed-loop system, virtually nothing is emitted to the

atmosphere. Moderate-temperature water is by far the more common
geothermal resource, and most geothermal power plants in the future will
be binary-cycle plants.
3.

Applications

The uses of geothermal energy in homes, farming, industry, infrastructure, and
electricity. Geothermal energy has more uses than you might imagine.
Basically, geothermal energy technology taps into subsurface areas where
desired temperatures exist. The uses of geothermal energy range depending on
the needs.

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RENEWABLE ENERGY
3.1. Uses of geothermal energy for houses
If you’re looking to cool your home in the summer, for example, one of the
uses of geothermal energy technologies is to allow you in hot times to take
heat from your house, send it down pipes into the ground (where it naturally
cools), and return it to your house (where it helps bring down the
temperature inside). The technology typically uses a liquid like antifreeze as
a carrier of that heat, which is moved about in a closed-loop piping system.
One of the other main uses of geothermal energy is the same concept but in
reverse in cold months. Geothermal energy technology is used to bring
warmer temperatures into your home without using fossil fuels, just by
tapping into a heat exchange deep below the surface of the earth. Cool,
right? But geothermal energy is so much more.

3.2. Uses of geothermal energy in farming
Some of the common uses of geothermal energy are amongst farmers, who
use geothermal energy to heat their greenhouses. Check this out (lemons
grown in the middle of winter!).
In Tuscany, Italy, farmers have used water heated by geothermal energy for
hundreds of years to grow vegetables in the winter. Hungary is also a major
user of geothermal energy, where eighty percent of the energy demand from
vegetables growers is met using geothermal energy technology.
Geothermal energy is also used in fish farms. The warm water spurs the
growth of animals ranging from alligators, shellfish, tropical fish,
amphibians to catfish and trout. Fish farmers from Oregon, Idaho, China,
Japan, and even Iceland use geothermal energy.

3.3. Uses of geothermal energy in industry
Industry is another consumer of geothermal energy. Its uses vary from
drying fruits, drying vegetables, drying wood, and dying wool to extracting
gold and silver from ore. Check out this cool graphic from the state

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RENEWABLE ENERGY
of California’s energy almanac for the varying temperatures needed for a
variety of industrial geothermal energy uses.

3.4. Uses of geothermal energy in infrastructure and electricity
Geothermal energy is also used to heat sidewalks and roads in order to
prevent freezing in the winter. Most recently, the Netherlands began using
geothermal energy to keep bike lanes from freezing in the wintertime, for
instance.

Geothermal power plants are also a good electricity generator:
•

Flashed Steam Plants — The water “flash” boils and the steam is used to
turn turbines.

•

Dry Steam Plants — These plants rely on the natural steam that comes
from the underground reservoirs to generate electricity.

•

Binary Power Plants —These plants use the water to heat a “secondary
liquid” which vaporizes and turns the turbines. The vaporized liquid is
then condensed and reused.

•

Hybrid Power Plants — In these plants, binary and flash techniques are
utilized simultaneously.

4.

Advantages and disadvantages of geothermal energy
4.1. Advantages
•

Significant Cost Saving : Geothermal energy generally involves low
running costs since it saves 80% costs over fossil fuels and no fuel is

used to generate the power. Since, no fuel is require so costs for
purchasing, transporting and cleaning up plants is quite low.

•

Reduce Reliance on Fossil Fuels: Dependence on fossil fuels
decreases with the increase in the use of geothermal energy. With the
sky-rocketing prices of oil, many countries are pushing companies to
adopt these clean sources of energy. Burning of fossil fuels releases
greenhouse gases which are responsible for global warming.

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RENEWABLE ENERGY
•

•

No Pollution: This is one of the main advantage of using geothermal
energy since it does not create any pollution and help in creating clean
environment. Being the renewable source of energy, geothermal energy
has helped in reducing global warming and pollution. Moreover,
Geothermal systems does not create any pollution as it releases some
gases from deep within the earth which are not very harmful to the
environment.
Direct Use: Since ancient times, people having been using this source
of energy for taking bath, heating homes, preparing food and today this
is also used for direct heating of homes and offices. This makes
geothermal energy cheaper and affordable. Although the initial

investment is quite steep but in the long run with huge cost saving it
proves quite useful.

4.2. Disadvantages
•

Not Widespread Source of Energy: Since this type of energy is not
widely used therefore the unavailability of equipment, staff,
infrastructure, training pose hindrance to the installation of geothermal
plants across the globe. Not enough skilled manpower and availability
of suitable build location pose serious problem in adopting geothermal
energy globally.

•

High Installation Costs: To get geothermal energy, requires
installation of power plants, to get steam from deep within the earth
and this require huge one time investment and require to hire a
certified installer and skilled staff needs to be recruited and relocated
to plant location. Moreover, electricity towers, stations need to set up
to move the power from geothermal plant to consumer

•

May Release Harmful Gases: Geothermal sites may contain some
poisonous gases and they can escape deep within the earth, through the
holes drilled by the constructors. The geothermal plant must therefore
be capable enough to contain these harmful and toxic gases.

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RENEWABLE ENERGY
•

Transportation: Geothermal Energy cannot be easily transported.
Once the tapped energy is extracted, it can be only used in the
surrounding areas. Other sources of energy like wood, coal or oil can
be transported to residential areas but this is not a case with
geothermal energy. Also, there is a fear of toxic substances getting
released into the atmosphere

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RENEWABLE ENERGY
VI.

CONCLUSION
To make sure we have plenty of energy in the future, it's up to all
of us to use energy wisely.
We must all conserve energy and use it efficiently. It's also up to
those who will create the new energy technologies of the future.
All energy sources have an impact on the environment. Concerns
about the greenhouse effect and global warming, air pollution, and
energy security have led to increasing interest and more
development in renewable energy sources such as solar, wind,
geothermal, wave power and hydrogen.
But we'll need to continue to use fossil fuels and nuclear energy
until new, cleaner technologies can replace them.

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RENEWABLE ENERGY

REFERENCES

VII.
1.
2.

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8. />9. />10. />11. />12. />13. />14. />15. />16. />17. />18. />4.

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