Thermal Solar Panel Protection

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Thermal Solar Panel Protection
Project Team Krista Miller Sohaib Hasan John
Helme
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What is the problem?

• Passive solar panels collect energy in the
  form of heat. In warm weather, it is possible
  for the temperature of these panels to exceed a
  desirable limit.

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Normal Solutions

• One solution is to dump hot water and add cold
  water.

• Another solution is to use a large thermal mass
  like a swimming pool or the earth.

These options are not always viable.
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Problem Statement

• The maximum temperature that a passive solar
  panel can reach must be controlled.
• The temperature control system must work without
  using additional water.
• When not active, the control system shall not
  interfere in the efficiency of the solar panels.

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Solution Constraints

• The solution must
• Work on any number of panels.
• Have both an automatic and manual control.
• Have user adjustable temperature setting.
• Have a maximum cost of 200 per panel.

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Summary of Solutions
Solution Resolves Problem Economically Feasible Conserves Energy Uses Electro-mechanical systems
Dump heat into ground Yes No No No
Sterling Engine No limited heat dissipation Unknown Yes Yes
Seebeck Device No limited heat dissipation No Yes Yes
Energy Blocking Yes Yes No Yes
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Solution Statement

• Blinds will be automatically positioned to
  cover a solar panel before the panel temperature
  reaches a critical level.
• Each solar panel will
• Have a complete and independent blind system.
• Have adjustable temperature controls.
• Be controlled by a single override control.

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System Diagram
Position Sensors 1-3
Temp Sensor
Increment Motors
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Mechanical System Diagrams

• Solution allows for some play with the
  universal joint wont bind as easily.

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Mechanical Linkage

• Constructed From
• Pulley or Gear
• 2 machined spacers
• Connector to Solar Panels (pre-fabricated)
• Screws
• but will it hold up to our motor forces?

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Stress Tests Affect of a Motor on Assembly Parts
Safety Factor gt200 for each piece Deformities
Shown on a 50001 scale
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Cover

• Heavy Duty Premium White Tarp
• Blocks Sunlight
• Water-resistant
• Rot-proof
• Dust-proof.

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DC Motors Motor Driver

• Motor
• Denso 730557-7030
• 12V, 3.3A
• 163 RPM
• 100 oz in torque

• Motor Provides
• 100ozin 2.84 Nin
• Motor Requirements
• Torque test using spring scale
• Starting Torque 2.0 Nin
• Continuing Torque 1.0 Nin

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Electrical System Diagram
Microcontroller
Power Supply




Signal Conditioning/CJC
Signal Amplification
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Electronics Overview

• Microcontroller
• Freescale HCS08
• 10bit A2D converter
• Ease of use
• Inexpensive
• Available Code

• Position Switches
• SPST Momentary Roller Switch

Open Limit Switch (in back)
Covered Limit Switch
Mid Position Limit Switch
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State Diagram
Microswitches Panel open Panel 1/2 open Panel
closed Thermocouple Temperature
Motor close Motor open
Override Switch Open Close
Reference Variables Standard close
temperature Critical close temperature Standard
open temperature These values will be set
using potentiometers on the controller circuit.
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Budget for Major and Minor Components
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Schedule, Personnel Assignments, Milestones
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Summary

• Problem
• The temperature of the solar panels must not
  exceed a maximum temperature.
• Constraints
• Must work on any number of panels.
• Must have both an automatic and manual control.
• Must have a maximum cost of 200 per panel.

• Solution
• Solar panels will be automatically covered
  when they reach a set temperature.
• Solution Constraints
• Controller and motor for each panel.
• Open, close and power off override controls.
• Demonstration system estimated cost of 185.

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For More Information

• Our Website
• http//www.vtc.edu/elm/projects/2006-2007/Adaptive
  _Maze/New20Website/index.htm
• AET Solar Panel Website
• www.aetsolar.com