HRS: Heat Reclamation System
Aleksey Treskov
Evan Lamson
Sarita Gautam
Wyatt Mohrman
Tegan Argo
Eamon Mcmillan
Faisal Albirdisi
Mission Statement
• The objective of our project is to
transfer the heat energy created
by the internal resistance of
computer components into a state
where the energy can be
recollected in the form of
electricity. In addition, we will be
able to increase the processing
power of the computer.
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
Vision
•
Efficiently dissipate heat from the computer
•
Capture energy that is lost by the computer
•
Charge an electronic device using reclaimed
energy
•
Manipulate computer clock speed
•
Monitor the system functionality using an
Android device
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
Goals
• Low Level
– Basic Heat Transfer Pipeline
– Constructing the Case
• Mid Level
– Display monitoring system temperatures,
clock rates, and power generation
– Control system to maintain best possible
temperature difference
– Maximize power generated
• High Level
– Fully automated control of clock speed,
flow rates, and power generation.
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
Background
• Computer cooling is required to
remove waste heat from computer
components to keep them within
permissible temperature limits.
• Traditional Method
– Combination of heatsinks and fans
• Fans are used to cool the heatsinks that take heat away
from computer components
• Liquid Cooling Method
– Water Cooling System
• Circulates water through a cooler to absorb heat from the
CPU and then to a radiator to be cooled back down
– Submerge in Oil
• Completely submerge the computers components in a
non-conducting liquid to absorb the heat
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
Why Mineral Oil ?
• Non-conductive.
• Specific heat of 1.67 kj/kg°k (1.012 for
air)
• Thermal conductivity of .133 w/m°k
(0.0257 for air).
• Easily accessible.
• Several industrial applications.
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
Why Thermoelectric Generators?
•
Industry already uses it in waste heat
recovery applications
•
They’ve been around for a while ( not a new
technology).
•
Easy to implement ( You only need a
temperature differential).
•
A way of harnessing thermal energy w/o
building a steam engine.
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
How?
System Block Diagram
Power
Desktop PC
Computer
TEG Power
Reclamation
DC Power
Control System
User
Display
Data
Visualization
Control System
Level 2 Functional Decomposition
Thermal Sensors
Pump Control
Flow Rate Sensor
Computer
Control
Clock Speeds
User data
µController
Bluetooth
module
Control System
Input
•
Thermal Sensors
Thermal sensors
– Heat Differential
Flow Rate Sensor
• Two Diodes to monitor Hot and Cold side
Temperatures
Clock Speeds
µController
– Operating Maximum
• Hot side diode and computer built in
temperature sensors
•
Flow Rate Sensors
–
–
•
•
User data
Flow Rate
Pump Speed Voltage
Clock Speeds
– Current processes Clock Rate
– Fan Operating Speed
User Data
– Serial input from paired Bluetooth
device
• State Change
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
Bluetooth
module
Control System
Output
•
Pump Control
• Asserts a 0-3.3v PWM signal to vary pump rate
•
Computer Control
• Outputs serial communication to interact with
computer
• Outputs Control Signal to change Clock Speed
• Outputs Power On / Off Signal
•
Data Output
• Temperature readings
• Successful state changes
• Current Operating mode
Thermal Sensors
Pump Control
Flow Rate Sensor
Computer
Control
Clock Speeds
User data
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
µController
Bluetooth
module
Control System
Implementation
To handle the various I/O communication present in
our project we have selected to use a µController in
conjunction with Bluetooth Module.
• µController
• Arm Cortex Microcontroller
• Capable of capturing and asserting all
control related signals
• Low Power Operation (Suspended
operation)
• Familiarity
• Bluetooth Module
• Blue Tooth Radio (RN-BlueSMiRF)
• Android Compatible
• Low Cost
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
Control System
• High Risk Components
The Largest Problem associated with our Control
system is timing. We are required to capture
several input output signals, change states
accordingly, while outputting display data.
• To solve this problem a second
microcontroller may be added to allow
parallel polling of various sensors.
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
Thermoelectric Generators
•
Heat is carried by holes in P
type, electrons in N type.
•
Across each junction a small
voltage is produced.
•
Place many of these in series
to get useful voltage.
•
Heat -> DC Volts
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
TEG resistance varies with temperature
•
•
Typically between 1.8 to 3.3 ohms per TEG
module.
Problem with using semiconductors is the
internal resistance.
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
Maximum power transfer theorem
•
In order to get the most power from the TEGs
we must match the load resistance to the TEG
internal resistance.
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
Basic Energy Harvesting MPP
•
MPP converter matches our load impedance
(battery for example) to TEG internal
resistance over different temperature ranges.
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
Duty cycle controlled MPP
•
The load voltage (and resistance) is
transformed with the MPPT according to the
duty cycle. When a duty cycle is chosen such
that the load resistance equals the TEGs
internal resistance, maximum power is
transferred.
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
Study Results**
•
MPP tracking improves TEG power generation
by more than 15% over direct charge.
**Development of a
thermoelectric batterycharger
with microcontrollerbased maximum power
point tracking technique
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
*Jensak Eakburanawat
*Itsda Boonyaroonate
Display
•
Android interface 4.0
– Previous experience
– Open Source
– GraphView library
•
External monitor
–
•
MatLab
Display
– Temperature data
– Power reclamation data
– Clock speed of the computer
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
Bluetooth Radio (RN-BlueSMiRF)
•
45x16.6x3.9mm
•
Hardy frequency hopping scheme - operates
in harsh RF environments like Wi-Fi, 802.11g,
and Zigbee
•
Operating Temperature: -40 ~ +70C
•
Operating Voltage: 3.3V-6V
•
Transmitting distance 18 meters
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
Testing
• Two identical systems in two different
environments.
• Compare processing powers with
operating temperature.
• Compare overall energy savings
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
Overview
System Roles and Responsibilities
Responsibilities
Roles
HW/SW
Check CPU temps
System Check Module (SCM)
HW : On-board temp. sensors
SW : Send data to CSA/FRA
Check fluid temps
System Check Module (SCM)
HW : Digital therm. Sensors
SW : Send data to CSA/FRA
Increase/Decrease Clock
Clock Speed Adjustor (CSA)
SW : Compare temps to optimal settings, send command to overclocking program
(PC)
Pump fluids
Flow Rate Adjustor (FRA)
HW : Micro-pumps
SW : Compare temps to optimal setting, send pwm signal to pumps
Switch Modes
Mode Select
HW : Touchscreen interface
SW : Run benchmark utility depending on which mode user has selected.
Display Data
Grapher
HW : Android device / LCD display
SW : Collect temperatures, clock speed, and pump speed data; display current
readings and real-time historical graphs
Maintain Safety
Safety Module
HW : Servo-controlled case vents, pressure release valve, GFI
SW : Compare temperatures with maximum levels; increase flows, decrease
clock, and/or open vents as needed
Harvest Energy
TEG Array Module
HW : TEG's, power converter, battery
Track MPP
MPP Tracker
HW : Interface with power converter
SW : Detect and operate at MPP duty cycle
Send/Receive Data
Communications Module
HW : RN-42 Bluetooth
SW : Encode data for transmission to Android App
Overview
System Diagram
Overview
System Diagram: Display
Overview
System Diagram: Control
Overview
System Diagram: Power Circuit
Constraints/Limitations
• Max operating temp: ~90°C
• Max TEG efficiency: ~10%.
• Maximum Clock Rate
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
Risks and contingency plan
Risks
• Overheating of components
• Inadequate temperature differential
• Occurrence of ground fault
• Timing Constraints
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
Contingency Plan
In case of overheating:
• Decrease the clock speed.
• Increase the flow rate of cold oil.
In case of inadequate temperature differential:
• Increase the clock speed (Hotter hot side).
• Increase the cold water flow rate ( Colder
cold side)
Risk of ground fault:
• Plug the equipment into a GFCI (Ground fault
circuit interrupter) protected outlet.
For timing constraint:
• Additional processing by adding a second
microcontroller.
Tegan Faisal
Eamon Wyatt
Aleksey
Evan Sarita
Schedule: Fall Semester
Schedule: Spring Semester
Budget
Component
Item
Quantity
Sub
Total
Total
Power Reclamation
System
LM95234 Quad Temp Sensor
3
$3.25
$9.75
Heat Sync and thermal pipe
TEG Power Generation Module
(1261G-7L31-04CL)
PCB Board
1
8
$30.00
$30.00
$30.00
$240.00
1
$40.00
$40.00
Misc. PCB components (resistors,
caps, etc.)
1
$15.00
$15.00
DC-DC Power Converters
8
$23.50
$188.00
Arm Cortex Microcontroller
LPCXpresso Development Kit
1
$60.00
$60.00
PCB Board
Misc. PCB components
(resistors, caps, etc…)
1
1
$40.00
$15.00
$40.00
$15.00
Display
Bluetooth Radio (RN-BlueSMiRF)
1
$29.00
$29.00
Test/Control
Computer
Motherboard (MSI A55M-P33 FM1)
2
$49.99
$99.98
CPU (AMD A6-3500 Llano 2.1GHz
FM1 65W )
Ram
2
$69.99
$139.98
2
$20.00
$40.00
ATX Power Supply(COOLER MASTER
Elite 460)
2
$30.00
$60.00
Hard Drives
2
$40.00
$80.00
Micro Hydro Pump
Acrylic Plexiglass (0.25” x 46” x 98”)
1
1
$30.00
$200.00
$30.00
$200.00
Control System
Misc.
Total:
$1,316.71
Division of Labor
Component
Primary
Secondary
Heat Reclamation System
Heat pipe
Wyatt
Eamon
Fluid Transport
Eamon
Evan
Dry Transport
Wyatt
Eamon
TEG array design
Wyatt
Faisal
Case design
Evan
Aleksey
Interface /Sensor
Microcontroller
Wyatt
Evan
On screen display
Wyatt
Sarita
Software
Aleksey
Evan
PCB Design
Faisal
Aleksey
Safety Electronics
Tegan
Evan
Power Electronics
PCB Design
Evan
Faisal
Circuit Design
Faisal
Evan
DC-DC Boost
Faisal
Tegan
TEG MPP Tracking
Aleksey
Wyatt
Project Management
Budget
Wyatt
Tegan
Documentation
Sarita
Tegan
Questions
Extra Slides
Here Be A 3 Headed Dog!!!
Constraints/Limitations
•
Max operating temp: 100°C
•
Max TEG efficiency: 10%.
Energy Harvesting
•
ΔT ≈ 70°C
•
V = [volts]
•
MPP tracking.
•
Cascaded Buck-Boost Converters
•
V_ο = [volts]
I = [amps]
I_ο= [amps]
Safety
•
Pressure control Valve
•
Emergency Shut off
•
Automatically activated vents
Control System
Thermoelectric Generators
•
•
•
•
•
TEG’s
– Efficiency 5-10%
– Simple to implement
Seebeck effect
Peltier effect
Thomson effects
Uses
– Cars
– Solar Cells
– Spacecrafts
Micro Hydro Pump