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EMERGY & ENERGY SYSTEMS. Session 1 Short Course for ECO Interns, EPA and Partners. Energy/ecology/systems Energy language systems diagrams Fundamental emergy concepts Emergy evaluations Emergy and economics Evaluating tangibles Evaluating information. Ratios and interpretations
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EMERGY & ENERGY SYSTEMS Session 1 Short Course for ECO Interns, EPA and Partners
Energy/ecology/systems Energy language systems diagrams Fundamental emergy concepts Emergy evaluations Emergy and economics Evaluating tangibles Evaluating information Ratios and interpretations Scale and boundary definition Spatial emergy concepts Emergy as decision tool Comprehensive state and regional evaluations State and regional case studies Topics Introduced
GOALS • Diagram a complex system network using energy systems language symbols • Aggregate diagram to answer a question • Identify data required for evaluation • Understand conversion of raw data into kinetic or potential energy amounts • Understand theory of emergy ratios and how to choose the right one
Energy and Ecology Goals for this unit • Hierarchy and concentration • Natural patterns • Thermodynamic Laws • Measurement: heat, work • Flows and forces • Available, free, dispersed energy • Limiting factors and interactions • Maximum power principle
HierarchyFood Chains and Pyramid Charts Carnivores Grazers Plants Sun More quantitative perspective
HierarchyFood Chains and Pyramid Charts Think left to right
Hierarchy Less available energy Concentrated and able to do more work Heat Sink Entropy Dissipated Energy
Concentration Water,CO2 Fertilizer O2, H2O O2, H2O
Concentration Force Force 100 10 Consumer 1 1000 Force 10 Producer 100 Consumer 1110 (1109)
Patterns - point source • Wells • Springs
Patterns - line source • Coast • Highway • River
Patterns - Planar • Sun • Rain
Patterns – combined sources • Point and line
Thermodynamic Laws First law of thermodynamics Law of Conservation The total energy of any system and its surroundings is conserved. • i.e.Energy is neither created nor destroyed, it changes from one form to another. dU = dQ - dW
Thermodynamic Laws The Second Law of Thermodynamics The entropy change of any system and its surroundings, considered together, resulting from any real process, is positive and approaches a limiting value of zero for any process that approaches irreversibility. dS = dQrev/T; S = K*log(N) dS = dSsystem + dSsurroundings
Forms of Energy • light • chemical • mechanical • heat • electric • atomic • sound
Theoretical Energy • Potential stored energy of position • Gravitational PEgrav = m*g*h • Elastic PEspring = ½*k*x2
Theoretical Energy • Kinetic KE = ½*m*v2 energy of motion • vibrational • rotational • translational
Theoretical Energy • Gibbs Free dG = dH –d(TS) G – G0 = RT ln fi f0 fi,0 = f(molarity of solutions)
Energy Terms • Heat Temperature • Work W = F(orce) x D(istance) x cos N • How far does it move • How hard to get it there
Energy Terms • Power Rate at which work is done Power = work time
Energy Terms • Units of measure Joule (J) – kg*m2/s2 Newton (N) – kg*m/s2 Kilowatt (kW) – 1000J/s
Energy and Ecology Terms • Limiting factors • Interactions • Stress reactions
Maximum Power Principle • Systems prevail that develop designs that maximize the flow of useful energy. Lotka, 1922 Autocatalytic feedback
Maximum Power Principle • When energy inputs are low, no feedback or storage develops and energy is dispersed. No feedback or storage
Dimensional analysis 1bbl oil x 42 gal x 1.26E5 BTU x 1055 J = 5.6E9 J bbl gal BTU Energy Conversion
Dimensional analysis 1bbl oil x 42 gal x 1.26E5 BTU x 1055 J = 5.6E9 J bbl gal BTU x x
Dimensional analysis 1bbl oil x 42 gal x 1.26E5 BTU x 1055 J = 5.6E9 J bbl gal BTU x x x x
Dimensional analysis 1bbl oil x 42 gal x 1.26E5 BTU x 1055 J = 5.6E9 J bbl gal BTU x x x x x x
Practice conversions using dimensional analysis 1.2E6 gal water to grams Average of 56 KW electricity every hour for one week to J 1.3 short ton bituminous coal to J 112 bushels cucumbers to J 100 lb 10-9-11-5 fertilizer to grams P, grams N and grams K Energy Conversion
Check Your Conversions Check mine, too 1.20E6 gal H2O x 3785.4 cm3 x 1.00 gram H2O = 4.54E9 grams H2O U.S. gal cm3 H2O 56.0 KW x 1 week x 168.0 hours x 3.6E6 J = 3.4E10 J hr week KWH 1.3 tons x 2000 lb x 13,500 BTU x 1055 J = 3.7E10 J short ton lb bituminous BTU 112 bushels X 55 lb x 454 g x (1-0.964) x (0.24*24 KJ + 0.04*39 KJ + 0.72*17KJ) x 1000J = 1.97E9 J bushel lb g g g KJ 100 lb fertilizer x 454 grams x 0.09g P2O5 x 62 gmoles P = 1784 gP lb g fert. 142 gmoles P2O5 100 lb fertilizer x 454 grams x 0.1g N x = 4540 gN lb g fert. 100 lb fertilizer x 454 grams x 0.11g K2O x 78.2 gmoles K = 2750 gK lb g fert. 142 gmoles K2O