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Mechanical EngineeringME562Sustainable Energy:
an Exergy Analysis
ME 562: Sustainable Energy – an Exergy Analysis Spring 2014
Exergy, environment and sustainability
Exergy, environment & sustainability 2/16
Mechanical EngineeringME562Sustainable Energy:
an Exergy Analysis
Energy and economy: the 1970s“Tonight I want to have an unpleasant talk with you about a problem unprecedented in our history. With the exception of preventing war, this is the greatest challenge our country will face during our lifetimes. The energy crisis has not yet overwhelmed us, but it will if we do not act quickly.
It is a problem we will not solve in the next few years, and it is likely to get progressively worse through the rest of this century.
We must not be selfsh or timid if we hope to have a decent world for our children and grandchildren.
We simply must balance our demand for energy with our rapidly shrinking resources. By acting now, we can control our future instead of letting the future control us....”
Jimmy Carter, April 18, 1977
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Mechanical EngineeringME562Sustainable Energy:
an Exergy Analysis
Oil price vs. GDP
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Mechanical EngineeringME562Sustainable Energy:
an Exergy Analysis
What about the environment?
“The good Earth — we could have saved it, but we were too damn cheap and lazy”
Kurt Vonnegut, from“A Man Without a Country” (2005)
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Mechanical EngineeringME562Sustainable Energy:
an Exergy Analysis
Acid rain
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Mechanical EngineeringME562Sustainable Energy:
an Exergy Analysis
Ozone depletion
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Mechanical EngineeringME562Sustainable Energy:
an Exergy Analysis
Climate change
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Mechanical EngineeringME562Sustainable Energy:
an Exergy Analysis
How do we cut GHGs?
http://www.sciencemag.org/content/335/6064/53.abstract
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Mechanical EngineeringME562Sustainable Energy:
an Exergy Analysis
What does it mean practically?
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Mechanical EngineeringME562Sustainable Energy:
an Exergy Analysis
Ouroboros and the 2nd lawOrder destruction and Chaos creation
● A low-exergy (disordered) environment is a degraded one
● Human value systems in some way are related to order
Resource degradation
● Resources not at equilibrium with the environment are valuable (e.g. a high-concentration ore)
● Resources with high reactivity are valuable (e.g. oil, natural gas)
Waste exergy emissions
● Wastes with high exergy have the potential to react with the environment
● High-exergy waste can interfere with other exergetic processes
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Mechanical EngineeringME562Sustainable Energy:
an Exergy Analysis
Exergy effciency and sustainability
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Mechanical EngineeringME562Sustainable Energy:
an Exergy Analysis
Four aspects of sustainability
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Mechanical EngineeringME562Sustainable Energy:
an Exergy Analysis
Exergy path to sustainability
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Mechanical EngineeringME562Sustainable Energy:
an Exergy Analysis
Issues in renewables deployment
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Mechanical EngineeringME562Sustainable Energy:
an Exergy Analysis
Typical steam plant layout
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Mechanical EngineeringME562Sustainable Energy:
an Exergy Analysis
Energy and exergy paths
