presentation on thermoelectricity

1. THERMOELECTRIC POWER
GENERATION
BY:
P.KIRANMAYI
DEPARTMENT OF EEE
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22-01-2015

2. CONTENTS
 Introduction
 Why Thermoelectricity ???
 Principle
 Working and Construction
 Material of choice for TEG
 Simulations
 Advantages and Disadvantages
 Applications
 Conclusion
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3. INTRODUCTION:
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THERMOELECTRIC POWER GENERATION
USING WASTE - HEAT ENERGY AS AN
ALTERNATIVE GREEN TECHNOLOGY
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4. 4
Why thermoelectricity ???
Increasing energy demand!!!
Increasing pollution!!!
Increasing IC heat!!!
Green energy production by
thermoelectricity.
Automobile waste heat thermoelectric
power generation.
On chip thermoelectric cooling.
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5. Why thermoelectricity ???
IEA,
WEO,
2008
Nasty Problems
Green energy
Production by
thermoelectricity
Automobile waste
heat thermoelectric
power generation
Choudhary et. al,
Nature nano. (2009)
On chip
thermoelectric
cooling (BiTe )
Green Solutions from thermoelectricity !!!
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6. PRINCIPLE
 SEEBECK EFFECT, PELTIER EFFECT.
 WORKING MECHANISM OF
A THERMOCOUPLE.
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7. SEEBECK EFFECT
S= dV / dT;
S is the Seebeck Coefficient with units of Volts per Kelvin
S is positive when the direction of electric current is same
as the direction of thermal current
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8. PELTIER EFFECT:
П <0 ; Negative Peltier coefficient
High energy electrons move from
right to left.
Thermal current and electric current
flow in opposite directions.
(electronic)
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9. PELTIER COOLING
П >0 ; Positive Peltier coefficient
High energy holes move from left to
right.
Thermal current and electric current
flow in same direction.
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10. WORKING
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Fig: schematic diagram of TEG.

11. Thermoelectric Materials
2
( )e g
T
ZT

  


- Seebeck Coefficient
- Electrical Resistivity
- Thermal Conductivity
e – Electronic
g – Lattice
Figure of Merit:
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12. Material of choice for
thermoelectricity
TE Parameters
Materials
Metals
Insulators
Semiconductors
Semiconductors most suitable TE material.
Allow separate control of G (electrons) and κ (phonons).
Electrical
Conductivity
(G)
Seebeck
Coefficient
(S)
Thermal
Conductivity
(κ)
High
~102 W/m-K
High
Moderate
10-3S/m
High
~120 μV/K
Very High
~107 S/m
Low
~ 10μV/K
Low
~10-2-10-4 W/m-K
Low
~10 W/m-K
Extremely
low (~10-10S/m)
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13. SIMULATIONS
 A TEG MODULE MODEL WITH INITIALLY 8
TEG MODULES WAS RUN
 THEORETICAL POWER OBTAINED –
56.347W
 POWER OBTAINED IN SIMULATION –
51.42W
 TO INCREASE OUTPUT NUMBER OF TE
MODULES INCREASED TO 18
 NEW OUTPUT – 122.67W
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14. ADVANTAGES AND
DISADVANTAGES
ADVANTAGES:
 Environmentally friendly
 Recycles wasted heat energy
 Scalability, meaning that the device can be applied to any size
heat source from a water heater to a manufacturers equipment
 Reliable source of energy
 Lowers production cost
DISADVANTAGES:
 TE material is expensive
 Structural failure of TE element at high temperatures
 Electrical resistivity increases 14
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15. 15
APPLICATIONS
Water Cooler
Cooled
Car Seat
Electronic Cooling
Laser Cooling
TE
Si bench
1 kW Generator for Diesel Truck
Demonstrated capability to produce
1 kW of
electric power from Diesel engine
exhaust.
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16. CONCLUSION
 THUS, BY USING TEG, THE WASTE HEAT CAN BE
USED TO GENERATE ELECTRICITY.
 SIMULATIONS AND EXPERIMENTS HAS BEEN
CONDUCTED AND MORE EFFICIENT SYSTEMS CAN BE
DEVELOPED IN FUTURE WITH NANOCRYSTALLINE
APPROACH.
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17. REFERENCES:
1. Thermo-electrics: Basic principles and New Materials Development by
Nolas, Sharp and Goldsmid
2. Thermoelectric Refrigeration by Goldsmid
3. Thermodynamics by Callen. Sections 17-1 to 17-5
4. Abram Joffe, “The Revival of Thermoelectricity,” Scientific American,
vol. 199, pp. 31-37, November 1958.

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