iPower: An Energy Conservation System for Intelligent Buildings by Wireless Sensor Networks

1
iPower An Energy Conservation System for
Intelligent Buildings by Wireless Sensor Networks

• Yu-Chee Tseng, You-Chiun Wang, and Lun-Wu Yeh
• Department of Computer Science
• National Chiao-Tung University
• yctseng, wangyc, lwyeh_at_cs.nctu.edu.tw

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Outline

• Introduction
• iPower System
• System Architecture
• Energy Conservation Scenario
• Message Flows in the iPower System
• Personalized Services and User Profiles
• Protocol Stack
• Implementation of iPower System
• Conclusions

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Introduction

• According to statistics
• more than 1/3 of energy consumption is spent on
  HVAC systems, which include heating, ventilating,
  air conditioning, and other related equipments.
• Energy saving
• exploit the context information of an environment
  to automatically control the usage of electric
  appliances

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iPower System

• iPower (intelligent and personalized
  energy-conservation system by wireless sensor
  networks) system
• reduce energy consumption of HVAC systems by
  exploiting the context-aware capability of
  sensors
• provide personalized services in which electric
  appliances can be automatically adjusted to
  satisfy users preferences.

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System Architecture (1/2)

• System architecture
• Sensor nodes
• Form a multi-hop WSN to collect information in
  the environment
• WSN gateways
• Four major functionalities
• issuing commands to nodes of the WSN
• gathering data from nodes of the WSN
• reporting the rooms condition to the control
  server
• maintaining the WSN
• Broadcast heart-beat messages periodically to the
  network
• sensor node will reply an alive message to the
  WSN gateway

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System Architecture (2/2)

• System architecture
• Control server
• collect the systems status
• make a smart decision to control electric
  appliance devices
• perform power-saving decisions
• Power-line control devices
• turn on/off or adjust the electric appliances
• User identification devices
• portable devices that can be carried by users so
  that the system can determine users IDs and
  retrieve their profiles

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Energy Conservation Scenario

• Scenario
• Room A electric appliances are turned on but
  nobody is in the room
• Room B electric appliances are turned on and
  somebody is in the room (with user identification
  device)
• Room C electric appliances are turned on and
  somebody is in the room (without user
  identification device)
• Room D electric appliances are turned on in a
  room with smart furniture.
• Room E electric appliances are turned off

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Message Flows in the iPower System
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Personalized Services and User Profiles

• Personalized Services
• Electric appliances can be automatically adjusted
  to satisfy users preference
• Create a profile in the servers database to
  record users preference
• User should carry a identification device

An example of user profile.
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Protocol Stack

• User layer
• Service layer
• Profile layer
• Sensor layer
• Actuator layer

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Implementation of iPower System

• Hardware devices
• MICAz mote
• X10 devices
• User Interface
• Monitor area
• Configure area
• Attribute area

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Conclusion

• iPower System
• energy conservation in an intelligent building
• provide personalized services
• automatically adjust electric appliances to
  users preference
• avoid unnecessary electric electricity
  consumption of the HVAC system
• turn off the unnecessary electric appliances
• achieve energy conservation