DATA & INFORMATION FUSION
DEFENCE TECHNOLOGY CENTRE
Energy-Harvesting Sensor Nodes
A. S. Weddell, N. J. Grabham, N. R. Harris and N. M. White
Electronic Systems and Devices Group
School of Electronics and Computer Science
University of Southampton
Energy Harvesting Sensor Node
To develop and demonstrate an integrated approach to power
management such that sensors within a sensor network are able to
manage their energy requirements, and harvest energy from the local
environment, whilst simultaneously coordinating their activities in order
to achieve system-wide aggregate goals.
Energy Harvesting Technologies
Evaluation of Energy
Harvesting Technology
D. Karatzas
31st March 2007
Supercapacitor Charging
Sensor node operating
from energy harvested
from ambient indoor
office lighting using a
70cm2 amorphous
silicon photovoltaic
module and a maximum
power point circuit.
3
Supercap Voltage (V)
Project Aims
2.5
2
1.5
1
Diode
Buck-Boost
0.5
0
0
5
10
15
20
25
30
35
40
Time After Startup (mins)
Energy Harvester
Power
Generated
Perpetuum (EM Vibration)
0.05 – 5.0 mW
25 – 100mg at 99Hz
Mide (Piezo Vibration)
0.01 - 0.5mW
250 – 300mg at 37Hz
Ferro Solutions (Vibration)
0.4 – 9.3 mW
20-100mg at 21Hz
Enocean (EM Force)
0.1 – 0.2 mWs
Actuating force 2±0.5N/2mm
1.5 – 5.7 W
Temperature difference: 100C
Tellurex (Thermoelectric)
Tellurex (Thermoelectric)
Schott (PV Module)
Notes
40µW
Temperature difference: 5C
12mW / cm 2
12% efficiency, full sunlight
Typical power output of energy harvesting technologies.
PV Energy Harvester
EM Force
Vibration Energy Harvester Circuit
RF
Piezo Vibration
EM Vibration
PV Module
Evaluation
Solar
Panel
Energy
Conditioning
Vibration
Harvester
Energy
Conditioning
Energy
Monitoring
and
Switching
Energy
Store
CC2431
Perpetuum Harverster tested at 5.0V Output Voltage
500mg
250mg
100mg
50mg
Energy
Bleed
25mg
Local
Sensor
Local/PC
Display
16.0
14.0
Output Power (mW)
Empirical evaluation of
vibration harvesting
technology – power output
against input frequency.
Thermoelectric
Energy harvesting node is designed
in a modular manner, enabling the
interchange of energy harvesting
technologies to suit available
environmental energy. Modules
incorporate electronic data sheets
identifying the key parameters of the
source. Demonstrated using PV and
vibrational energy harvesters.
Energy Harvesting Node Architecture
12.0
10.0
8.0
6.0
4.0
To demonstrate the
energy harvesting
node’s capabilities it
has been deployed in
a simple three-node
network.
2.0
0.0
90
92
94
96
98
100
102
104
106
108
Drive Frequency (Hz)
MIDE Volture Tested at 5.0V output voltage
300mg
250mg
200mg
150mg
100mg
100mg
1.8
Three-node network incorporating energy-harvesting node
1.6
Output Power (mW)
1.4
1.2
1.0
0.8
References
0.6
0.4
0.2
0.0
36
36.5
37
37.5
38
38.5
39
39.5
40
40.5
41
41.5
Drive Frequency (Hz)
Embedded Software
Integrated approach to communication, sensing
and energy management through separate stacks.
Implementing an energy-aware sensor based on
the Chipcon CC2431 System on Chip.
1. A. S. Weddell, N. R. Harris, and N. M. White. Alternative energy sources for sensor nodes:
Rationalized design for long-term deployment. In Proceedings of the IEEE International
Instrumentation and Measurement Technology Conference (I2MTC), pages 1370-1375, Vancouver
Island, British Columbia, Canada, 2008.
2. A. S. Weddell, N. J. Grabham, N. R. Harris, and N. M. White. Flexible integration of alternative
energy sources for autonomous sensing. In Proceedings of the Second Electronics SystemIntegration Technology Conference (ESTC), Greenwich, London, UK, 2008.
3. A. S. Weddell, N. R. Harris, and N. M. White. An efficient indoor photovoltaic power harvesting
system for energy-aware wireless sensor nodes. In Proceedings of the Twenty-Second
International EUROSENSORS Conference, Dresden, Germany, 2008.
Contact
2.4GHz IEEE 802.15.4 RF Transceiver
8051 MCU Processor
8 KB RAM
128 KB programmable flash memory
Low Power Sleep Modes
Location Engine (resolution of 0.5m)
Digital battery monitor
Alex Weddell, University of Southampton
42
CC2431 Datasheet, Rev. 2.01, Texas Instruments, 2007
Prof. Neil M. White
nmw@ecs.soton.ac.uk
Electronic Systems and Devices Group
Electronics and Computer Science
University of Southampton
Highfield, Southampton, SO17 1BJ
www.difdtc.com