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History of Energy use, First look at history of temperature of the earth. demos. C8-31 measure human work. How did we get here?. A typical person can do work at a rate of about 100 Watts (J/s) Humans “burn” energy at a rate of about 1.6x10 13 Watts.
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History of Energy use, First look at history of temperature of the earth PHYS105: Physics for Decision Makers, Eno, F14
demos • C8-31 measure human work PHYS105: Physics for Decision Makers, Eno, F14
How did we get here? A typical person can do work at a rate of about 100 Watts (J/s) Humans “burn” energy at a rate of about 1.6x1013 Watts. World population is about 6x109 people. The US “burns” energy at a rate of 3.3x1012 Watts. The US population is 3.2x108 people. PHYS105: Physics for Decision Makers, Eno, F14
How did we get here? http://www.eia.gov/energyexplained/ PHYS105: Physics for Decision Makers, Eno, F14
History of Energy Use 100 W =3.6x103kcal/day Adapted from E. Cook, “The Flow of Energy in an Industrial Society”, Sci. Amer. 224, p. 136, 1971. PHYS105: Physics for Decision Makers, Eno, F14
Population Growth fire industrial horse water PHYS105: Physics for Decision Makers, Eno, F14
A person-power Demonstration of a person power (c8-13) A person is capable of generating roughly 100 W. Memorize this number. A typical American uses, on average, 100 person-powers, of energy. The US in total uses 30,000,000 person-power/ year. PHYS105: Physics for Decision Makers, Eno, F14
Burning Wood, Peat, etc prometheus PHYS105: Physics for Decision Makers, Eno, F14
Agriculture • Large growth in human population Mycene, 1600 bc PHYS105: Physics for Decision Makers, Eno, F14
Wind/Water • Whale oil • Coal • Steam engine • Irrigation via gravity • Wind/water • Destruction of European medieval forests 1100-1500 PHYS105: Physics for Decision Makers, Eno, F14
Industrial Era • Large scale air pollution due to coal burning Widnes, England, late 1800s PHYS105: Physics for Decision Makers, Eno, F14
Modern Era: Trends 115 people powers/ person U.S. Energy Consumption by Source Invention of steam engine PHYS105: Physics for Decision Makers, Eno, F14
History of earth’s temperature "All palaeotemps" by Glen Fergus - Own work. Licensed under Creative Commons Attribution-Share Alike 3.0 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:All_palaeotemps.svg#mediaviewer/File:All_palaeotemps.svg humans Land animals Extinction of dinosaurs, formation of Chesapeake Bay Notice the total range is about 20 degrees C ( 36 degrees F) But think how the environment has changed over that range of temperatures, from swamp of the Eocene age 66 million years ago, when there were forests in the artic and Antarctic, to ice age. PHYS105: Physics for Decision Makers, Eno, F14
What you should know • Know the 6 approximate technological stages for energy use and the approximate year they happened. Know approximately the ratio of power used per person compared to the power an unassisted person can generate for each era. • Know some environmental problems that occurred during eras prior to the current one. • Know approximately the total range of temperatures seem from 500 million years ago until the present. PHYS105: Physics for Decision Makers, Eno, F14