1. Day 3: Energy Generation Discussion 2
Energy Harvesting
Day 3: Energy Generation Discussion 2
April 17, 2013 Paul Nickelsberg Orchid Technologies Engineering and Consulting, Inc.

2. Energy Harvesting Review
Energy harvesting is the process of capturing trace amounts of naturally occurring energy from various sources.
Accumulating the Energy
Storing the Energy
Applying the Energy for Useful Purpose

3. Energy Generation Piezoelectric Energy Generation
Thermal Energy Generation
Chemical Energy Generation 3

4. Piezoelectric Energy Generation4

5. Piezoelectric Energy Generation
Applying mechanical strain to certain solid materials results in energy generation.
Courtesy Linear Technologies Corporation 5

6. Piezoelectric Energy Generation
Bending motion causes upper element to compress and lower element to stretch. Charge develops across each layer which counteracts the imposed strains.
X: Deflection Limit is proportional to Length²
Voc: Open Circuit Voltage proportional to X/L
Isc: Short Circuit Current
proportional to L x W 6

7. Piezoelectric Energy Generation
Reference: Seminario “RFId: sensors e energy harvesting” – LIUC Universita Carlo Cattaneo – 5 giugno 2009 7

8. Piezoelectric Energy Generation
Courtesy Mide Volture Data Sheet 8

9. Piezoelectric Energy Generation
(Factors: Frequency of Vibration, Amount of Piezo Material,
Tip Mass and G-Level)
Courtesy Mide Volture Data Sheet 9

10. Piezoelectric Energy Generation
(Factors: Frequency of Vibration, Amount of Piezo Material,
Tip Mass and G-Level)
Courtesy Mide Volture Data Sheet 10

11. Piezoelectric Energy Generation
Piezo Systems, Inc.
A lot of available power
Courtesy Piezo Systems Data Sheet 11

12. Thermal Energy Generation
Power generation caused by a thermal gradient between two dissimilar metals.
• Peltier Effect:
Heating or Cooling at Junction
• Seebeck Effect:
Energy generation at Junction
• Milliwatt Power Levels 12

13. Thermal Energy Generation - (TEG)
Courtesy Linear Technologies Corporation 13

14. Thermal Energy Generation - (TEG)
Voltage is proportional to temperature difference
The length and area of each elements sets its basic properties as thermal and electrical resistance
The P-N elements are connected in series in a module
Series connection gives higher voltage (and resistance)
From thermal point of view, they are connected in parallel 14

15. Thermal Energy Generation - (TEG)
System Thermal Model
Courtesy Linear Technologies Corporation 15

16. Thermal Energy Generation - (TEG)
System Thermal Model 16

17. Thermal Energy Generation - (TEG)
System Thermal Model
TEG Device
Heat Flow 17

18. Thermal Energy Generation - (TEG)18

19. Thermal Energy Generation - (TEG)19

20. Thermal Energy Generation - (TEG)
TEC ≡ TEG
an N-P pair is called a “couple”
Courtesy Linear Technologies Corporation 20

21. Thermal Energy Generation - (TEG)
High Efficiency 21

22. Thermal Energy Generation - (TEG)
Courtesy Marlow / Evergen 22

23. Thermal Energy Generation - (TEG)
Courtesy Marlow / Evergen 23

24. Energy Generation
Come back tomorrow 24