Energy Saving Thermostat

1
Energy Saving Thermostat

• Sponsored by the Michigan Public Service
  Commission
• February 14th, 2007

2
Economic Background

• 40 of national energy consumption is devoted to
  heating and cooling
• Michigan is the number one consumer of natural
  gas per capita
• The states yearly residential energy consumption
  is 92.5 billion kWh

3
ASHRAEAmerican Society of Heating,
Refrigerating, and Air-Conditioning Engineers

• Temperature, humidity and seasonal factors
  determine an individuals comfort level
• ASHRAE has developed a comfort standard
  incorporating these factors
• Currently available thermostats use only
  temperature to control Heating, Ventilation and
  Air Conditioning (HVAC) equipment

4
Our proposed product

• System will use ASHRAE comfort standard
• Two modules
• Universal plug and play interface
• Energy-conserving digital thermostat
• Easily expandable and upgradeable to work in the
  future with things such as an Intelli-grid or
  time of day pricing

5
Block Diagram
6
Design Specifics

• Evaluating both Microchip PIC and Cypress PSoC as
  microprocessors
• Sensirion SHT10 digital sensor for humidity and
  temperature
• USB flash reprogrammability
• I2C serial bus to reduce complex interfacing to
  only 2 wires
• Relays activated to request HVAC services

7
Demonstration of Capabilities

• System will be tested using Lansings humidity
  and temperature data from a previous year
• Compare project data to an existing home
  thermostat
• Energy use will be reduced by running HVAC
  equipment less
• Show that the energy consumption is less with our
  system

8
Risks and Rewards

• Advantages
• By using ASHRAE comfort index, energy use can be
  reduced
• Ensures compatibility and upgradeability with
  future advances in HVAC
• Universal interface reduces confusion of HVAC
  installation
• Disadvantages
• Humidity sensors are expensive
• Large initial roll-out cost