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Some Basic Concepts of Energy. Prepared for FYF 101J - Alternative Energy. Kenneth M. Klemow, Ph.D. Wilkes University. Overview of topics. Basic energy concepts Historic phases of energy production and supply Terminology pertaining to energy. Basic energy concepts. What is energy?.
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Some Basic Conceptsof Energy Prepared for FYF 101J - Alternative Energy Kenneth M. Klemow, Ph.D. Wilkes University
Overview of topics • Basic energy concepts • Historic phases of energy production and supply • Terminology pertaining to energy
What is energy? • Ability to do work • Physicists distinguish between kinetic and potential energy • Energy comes in different forms • Radiation • Mechanical energy • Chemical energy • Atomic energy • Electromagnetic energy • Electrical energy • Heat energy
How do we measure energy? • Force: Newton (N = kg x m / s²) • Energy: Joule (J = N x m) • Power: Watt (J / s) www.sommarskog.se
Is a Joule a lot or a little? • The energy released when an apple falls one meter to the ground. • The energy released as heat by a person at rest, every hundredth of a second. • # one hundredth of the energy a person can receive by drinking a drop of beer.
Some conversion factors • 1 calorie = 4.187 J • 1 BTU = 1054 J • 1 kilowatt hour = 3.60 x 106 J • 1 barrel oil equivalent = 6.119 x 109 J • 1 ton wood equivalent = 9.83 x 109 J • 1 ton coal equivalent = 29.31 x 109 J • 1 ton oil equivalent = 41.87 x 109 J • 1 quad (PBtu) = 1.055 x 1018 J • 1 horsepower = 735.49 W
Laws of Thermodyamics • First law: Energy cannot be created nor destroyed, can only be converted (conservation of energy) • Second law: No energy conversion is perfect; always get some loss as heat.
Energy and power • Power = energy / time • 1 watt - 1 Joule / second • Energy = power x time www.belmont.k12.ca.us
Energy Carbon reduction CO2 C6H12O6 H2O Carbon oxidation Energy Why is living matter a source of energy?
Energy needs • Biblical times • Move people and their possessions • Agriculture and food processing • Build cities • Produce clothing • Simple chemical transformations (e.g. metallurgy) • Heating www.uncp.edu
Where did this energy come from? • Animate sources • Humans • Animals • Low head hydropower • Biomass (woody tissue) www.uncp.edu
mhslibrary.org/ Energy needs • Industrial revolution times • Mechanized food production / consumption • Centralized heating • Transportation • Lighting • Textile manufacturing • More complex chemical processes (e.g., glass manufacturing)
mhslibrary.org/ Where did this energy come from? • Animate sources (mainly animals) • Low head hydropower • Biomass (woody tissue) • Coal • Petroleum • Low capacity wind
content.answers.com Why we need energy • Modern • Transportation (personal vehicles, commercial vehicles, aviation) • Automated production of goods • Transport of goods • Centralized heating and air conditioning • Lighting • Highly complex chemical processes
content.answers.com Where does this energy come from? • Coal • Petroleum • Natural gas • Nuclear fission • High and low head hydropower • Biomass (woody and herbaceous tissue) • Animate sources (mainly animals) • Low capacity and industrial wind • Geothermal • Solar collection
Terminology pertaining to modern energy • Renewable vs nonrenewable • Traditional vs new energy • Commercialized vs non-commercialized • Centralized vs distributed generation • On-grid vs off-grid
Stages of energy flowfrom http://www.fao.org/docrep/u2246e/u2246e02.htm • Primary energy is the energy as it is available in the natural environment, i.e. the primary source of energy. • Secondary energy is the energy ready for transport or transmission. • Final energy is the energy which the consumer buys or receives. • Useful energy is the energy which is an input in an end-use application.
Stages of energy flowfrom http://www.fao.org/docrep/u2246e/u2246e02.htm