St.
Kabir School DIA
Physics Investigatory project
Name- Ansh shah
Class- XII A
Roll no- 3
Content Page
no.
Certificate 2
Acknowledgment 3
Introduction 5
Theory 7
Construction and 10
working
Different types of 13
TEG
Advantages and 16
disadvantages
Applications 17
conclusion 18
Bibliography 17
Introduction
A thermoelectric generator (TEG), which is
also known as a seebeck generator, which
is a device that converts heat energy into
electrical energy.
So what is seebeck effect? It is the
principle discovered by Thomas Johann
Seebeck in 1821 which stated that when
there is a temperature difference
between two different conducting
materials, an
electric voltage is generated between
them.
When two different materials experience
a temperature gradient, charge carriers
(electrons or holes) diffuse from the hot
side to the cold side, creating an electric
potential difference. Thermoelectric
Materials: TEGs use semiconductor
materials that are specially designed to
have high thermoelectric efficiency. It is
essential for future generations to reduce
the quantity of global energy consumed,
and this can only be achieved through
technological development and use of
diversified renewable energy sources i.e.
solar wind, hydropower, in addition to
the energy sources currently used. Among
these different energy sources,
thermoelectricity is currently emerging as
a common and promising alternative
energy source for the future.
thermoelectricity (TE) in 1821 by
Seebeck, researchers have been trying to
understand and control this phenomenon.
Peltier did exactly this in 1834 by
discovering the opposite effect and Lord
Calvin in 1851 formulated the laws that
link these two phenomena. In the
following century, in 1909, Edmund
Altenkirch correctly calculated, for the first
time, the energy efficiency of a
thermoelectric generator now known as
figure of merit.
THEORY
Thermoelectric
modules: A typical TEG
module consists of between
ten and a hundred
thermoelectric elements of type n and
type p, electrically connected in series
and thermally in parallel, and
interposed between two ceramic
layers. When a temperature gradient
occurs between its two junctions,
the TEG converts thermal energy
into
electrical energy according to the
principle of the Seebeck effect. This flat
bulk architecture is the most widely
used and marketed.
Thermoelectric generator: The
thermoelectric generator is a device, where
electric energy is produced directly from
heat energy. They are also called Seebeck
generators since they used the Seebeck
effect to produce power. In conventional
power plants, like thermal power plants,
nuclear power plants, fuel is used to heat
the water. Generally, coal is burnt in that
process. After the water starts boiling,
and converted into steam, at high pressure,
this steam is used to rotate the turbine and
hence mechanical energy is converted
into electric energy by Fleming's law
of electromagnetic induction. In this
process, there is two-stage energy
conversion, first heat energy is converted
into mechanical energy and then
mechanical energy is converted to electric
energy. Because of this two-stage
process, the efficiency of the overall
system goes down. If we can directly
convert heat energy to electrical
energy, efficiency will be more. In the
thermoelectric generator, heat energy is
directly converted to electric energy,
which has high economic benefits.
Thermoelectric generators fundamentally
use the thermoelectric principle of
operation, which is based on the
temperature gradient.
Construction and
working of TEG
Construction:
Thermoelectric generators
are the devices that are
solid-state heat components
constructed of two essential
junctions which are p-type
and n-type. The P-type
junction has an increased
concentration of +ve charge
and the n-type junction has
an increased concentration
of -ve charged elements.
The p-type components are
doped in the condition to
have more positive charged
carriers or holes thus
providing a positive
Seebeck coefficient. In a
similar way, n- type
components are doped to
have more negative
charged carriers thus
providing a negative type
of Seeback coefficient. In
the thermoelectric generator
construction, the most
implemented element is
lead telluride. It is the
component that is
constructed of tellurium and
lead which have minimal
amounts of either sodium or
bismuth. In addition to this,
the other elements that are
used in this device
construction are bismuth
sulphide, tin telluride,
bismuth telluride, indium
arsenide, germanium
telluride, and many others.
With these materials,
thermoelectric generator
design can be done.
Working:
The thermoelectric generator working is
dependent on the Seeback effect. In this
effect, a loop that is formed in between the
two various metals generates an emf when
the metal junctions are maintained at
various temperature levels. As because of
this scenario, these are also termed as
Seeback power generators. A
thermoelectric generator is
generally included with a heat
source that is maintained at high
values of temperature and a heat
sink is also included. Here, the
heat sink temperature has to be
less than that of the heat source.
The change in temperature
values for the heat source and
heat sink allows the flowing
current across the load section.
The
output voltage and power values
can be increased in two ways.
One is by increasing the
temperature variation that rises in
between hot and cold edges and
the other is to form a series
connection with thermoelectric
power generators.The voltage of
this TEG device is given by V = αΔ
T.
Major
types of
thermoelectric
generators
Fossil-fuel generators
Generators have been
constructed to use natural
gas, propane, butane, kerosene,
jet fuels, and wood, to name but a
few heat sources. Commercial
units are usually in the 10- to
100-watt output power range.
These are for use in remote areas
in applications such as
navigational aids, data collection
and communications systems,
and cathodic protection, which
prevents electrolysis from
corroding metallic pipelines and
marine structures.
Solar source generators
Solar thermoelectric generators
have been used with some
success to power small irrigation
pumps in remote areas and
underdeveloped regions of the
world. An experimental system
has been described in which
warm surface ocean water is
used as the heat source and
cooler deep ocean water as the
heat sink.
Nuclear-fueled generators
radioisotope thermoelectric
generators provide electric
power for isolated weather
monitoring
stations, for deep-
ocean data collection, for
various warning and
communications systems, and
for spacecraft. In addition, a
low-power radioisotope
thermoelectric generator was
developed as early as 1970
and used to power cardiac
pacemakers. The power range
of radioisotope
thermoelectric generators is
generally between 10−6 and
100 watts.
Advantages and
disadvantages
Advantages:
Economically friendly
Reduces waste heat
A reliable source of energy .
Lower production cost
Disadvantage
s: Lower
efficiency
Limited applications
Requires a constant source of
heat Energy cannot be stored
Applications
ľkc applicatio⭲s of
tkcímoclcctíic gc⭲cíatoís
i⭲cludc tkc followi⭲g:
Electíonics
Space applications
Renewable eneígy souíces
Gas pipelines
Radio communication
Conclusion
Thermoelectric generators are an
intriguing way to generate
renewable energy directly from
waste heat. However, their
efficiencies are limited due to
their thermal and electrical
properties
being dependent on each other.
Nevertheless, their solid state
scalable technology makes
them appealing and even
more efficient in selective
applications.
Implementing thermoelectric
generators on vehicle exhaust
manifolds would help reduce
fuel
consumption, which in turn
would help preserve the world
natural
resources and reduce carbon
emissions. Thermoelectric
generators have proved their
usefulness in low and even
high- power devices, as well as
miniaturized and bulk
applications depending on the
generated power
range, materials, and
manufacturing process.
Many
applications were
introduced, as well as their
energy sources and cost
economic ratio, like
wireless
sensor networks (WSNs),
wearable and implantable
devices (IoT and medical
applications), industrial
electronic devices,
automobiles, and aerospace
applications.
Bibliography
Wikipedia.com
Google search engine
www.youtube.com
https://
www.watelectrical.co m
THANK
YOU
