Introduction to the Concept of Exergy

1
Introduction to the Concept of Exergy

• Masanori Shukuya
• Laboratory of Building Environment
• Musashi Institute of Technology

16th April 2003
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Why exergy concept?

• to articulate what is consumed for
• lighting, heating, cooling, and
• ventilation.
• to have a better knowledge for
• developing advanced built-
• environmental conditioning systems.
• - new types
• - passive and active combined

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1.
Energy is conserved through a whole of energy
transfer.
2.
3.
What is the so-called Energy Issue?
4
1.
Matter is conserved through a whole of mass
diffusion.
2.
3.
What matters beyond the conservation of matter?
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1.
1.
2.
2.
3.
3.
Entropy is generated while energy and matter are
conserved.
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Energy Conservation
Entropy Generation
Environmental Temperature
Exergy Consumption Theorem
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Exergy Balance Equation

• Exergy Input
• Exergy Consumed
• Exergy Stored
• Exergy Output

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Energy, Entropy, and Exergy Flow through a
Building Wall
Energy
Exergy
Entropy
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Exergy-Entropy Process
Exergy

• Feed on exergy
• Consume exergy
• Generate entropy
• Dispose of entropy

Entropy
Exergy
Entropy
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The environmental systems as nesting structure
Exergy
The Universe
Global Environment
Regional Environment
Urban Space
Built Environment
Room Space
Entropy
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Human-Body Exergy Consumption and Surrounding
Temperatures