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Emergy Short Course Syllabus

Curriculum for a two week emergy and systems concepts short course

This course was created largely through the efforts of Sherry Brandt-Williams, EPA Post-Doctoral Fellow, 2002-2005, in collaboration with Dan Campbell, Research Ecologist

Sessions in the Course and Materials

Session 1: Introduction to Emergy and Systems Ecology
Session 2: Introduction to Systems Diagrams
Session 3: Introduction to Emergy
Session 4: Emergy Evaluations

Tax Credit
Session 5: Emergy and Economics
Session 6: Evaluating Tangibles
Folio 1: Introduction and Global Budget
Folio 2: Emergy of Global Process
Folio 3: Emergy of Ecosystems
Folio 4: Emergy of Florida Agriculture
Session 7: Evaluating Information
Session 8: Ratios and Interpretations
Session 9: Scale and Boundary Definitions
Session 10: Emergy Applications

Caveat: Transformities and energy data used in this course are from historical studies and do not represent consistent values to use in new studies. For more information see Odum (1996) and Campbell et al. (2005) at http://www.epa.gov/nheerl/download_files/publications/wvevaluationposted.pdf and the web site associated with this report: http://www.epa.gov/aed/research/desupp3.html

Diagrams in this course are for illustrative purposes only. For best diagramming practices see Odum (1996) and Odum (1994). The Ecuador example is from Odum and Arding (1991) and the Thailand example is from Brown and McClanahan (1992).


Session 1: Getting everyone on the same energy/ecology/systems page
Introduction: Energy and ecology

Hierarchy and concentration (use foodwebs and pyramids since universally recognized)
Patterns (provides tangible link to experience from everyday observations)
Measurement: heat, work
Flows, force
Available, free, dispersed
Maximum power principle
Limiting factors, interactions

Session 2: Learning a New Language
Introduction: Systems Diagrams

Boundary definitions, driving forces
System components
Structure in symbols
Function in pathways
Why this system is preferable to others (Forrester, Stella for example)

Discussion and exercise

Diagram a personally well known system

Session 3: Introduction to emergy
Diagram follow-up

Aggregation to answer a question (continue use of initial system introduced, still no internal modeling depicted)
Aggregate one diagram to a single line of components and paths
Estimate actual energy and material flows along that path including sinks

Introduction: Emergy

Definitions: emergy, transformity, empower
Main system concepts: no loss along paths, inputs and outputs versus internal processes, recycle
Apply to single line energy diagram, showing cumulative emergy calculation, transformity calculations
Redraw energy diagram as emergy diagram

Fundamental emergy budgets and human interfaces

Main energy sources
Coupled sources
Explanations of calculations for these items
Environment-economic interface
Services versus goods, raw materials, energy
Renewable, non-renewable, purchased
Emdollar concept

Discussion and exercise

Aggregate own diagram, estimate energy flows, look up emergy transformity values and calculate input and output emergy and transformity values (assist in getting aggregation down to single line, while retaining a slightly more complex version for net benefit work coming up)

Session 4: Emergy evaluations
Tables and metadata

Key table components
Matching the table to a diagram
Identifying components to be included
Different tables for different purposes: transformity, net benefits, alternatives, storages
Notes as metadata

Calculations and locating data

Converting data to joules and grams
Insuring accurate representation (dry versus wet weight, active versus inert ingredients, double counting coupled sources, etc.)
Physical and chemical conversion calculations
Finding and confirming raw data
Using money as input value: problems and reality
Using rates of production versus storage times

Discussion and Exercises

Choose two different questions to explore with personal diagram, one resulting in a transformity and the other a net benefit. Label diagrams appropriately and create three emergy evaluation tables: transformity, storages, and net benefits. Locate data in books provided or on internet if connections available. Convert to emergy with available transformities or estimates we provide if necessary. Calculate transformity of some key item.

Session 5: Emergy and economics

Calculation for US
Compared to exchange rate for other countries
Use of emergy to update old economic data

Cross boundary exchange

Calculating benefits/deficits
Raw materials versus finished goods
Implications for trade policy

Loans, interest, assets, capital, operating expense

Calculating contribution to annual rate of production for evaluation tables

Discussion and Exercises

Provide sample questions related to calculation of international exchanges. Calculate emergy ratios and exchange rates. Add economic interface to own diagram if not already there.

Session 6: Evaluating tangibles
Renewable and non-renewable energy resources

Calculations for tides, waves, etc.
Elements and compounds (lead, phosphorus, potash, etc.)

Natural Systems


Purchased and processed materials

Electric power

Discussion and Exercises

Discuss transformities representative of natural systems: multiple? single?
Discuss geographic and process differences and effects on transformities.
Provide sample diagrams of systems and processes with energy, material and money data. Create one emergy table each for transformity calculation and overall evaluation. Using transformities presented, choosing appropriately, complete evaluations.

Session 7: Evaluating information
Genetic and learned information, human services

Different levels of education
Labor, experts

Biodiversity, endangered species, antiquities

Copies versus first
One of a kind
Cultural evaluations

Discussion and Exercises

Discuss other ways to evaluate information, labor and services.
Provide sample diagrams of systems and processes with energy, material, information and money data. Create one emergy table for overall evaluation. Using transformities presented, choosing appropriately, complete tables.

Session 8: Emergy algebra, ratios and interpretations
Network algebra, abridged


Ratios and interpretations

Definitions and purposes of key ratios
Comparison of relative values for different countries and systems/processes
Calculate ratios for example system

Discussion and Exercises

Calculate emergy networks on sample diagrams we provide
Try to calculate one of the less aggregated diagrams from personal exercise
Calculate ratios from own diagram and evaluations
Present ratios and possible reasons for ranking of values in comparison with other evaluation.

Session 9: Scale and boundary definition
Effect of scale on net benefits

Geographic versus political

Empower density and support area

Definitions and calculations
Interpretation of comparative ratio values
Combining with investment ratio to plan new development locations
Other applications
Comparison to footprint evaluations

Time scales

Short term versus long term, human versus geologic
Cumulative versus single event
Compare emergy to life-cycle evaluations

Discussion and Exercises

Provide verbal descriptions of processes or systems providing energy, material and money data. Provide several questions that will require diagrams drawn at different scales. Create one emergy table, then define the components necessary to complete a net benefit evaluation for each question. Set up the equation for each net benefit and calculate. Discuss the comparative values and their implied policies.

Session 10: Emergy applications
Evaluating alternative plans

Diagrams and ratios
Economic incentive evaluations
Environmental damages

Case studies

Thai dams
Ecuador shrimp

Identifying important components

Basic components
Environmental issues
Economic issues
Social and cultural issues

Using assumptions, interpolations, extrapolations

Converting difficult or abstract data
Data sources

Case studies

West Virginia, http://www.epa.gov/nheerl/download_files/publications/wvevaluationposted.pdf

Discussion and Exercises

Discuss ways to evaluate social and cultural issues.
Provide verbal descriptions of a small political region providing energy, material and money data. Set up table and convert information into data that can be used to calculate emergy. Create notes explaining conversion calculations. Compare differences in strategy between interns.
Discuss differences in evaluations and implications concerning completeness, lack of bias, scale issues. Compare results for key ratios between studies presented and discuss implications.
Provide description of issue with alternative solutions, and data necessary to evaluate. Draw simple diagram and create emergy evaluation tables. Using all ratios and methods introduced this week, present a case for selecting a particular alternative. Did they all arrive at the same conclusion? Discuss differences.


Campbell , D.E., Brandt-Williams, S.L., and Meisch, M.E.A., 2005. Environmental Accounting Using Emergy: Evaluation of the State of West Virginia. EPA/600/R-05/006.

Brown, M.T. and T.R. McClanahan 1992. Emergy Analysis Perspectives of Thailand and Mekong River Dam Proposals. Report to the Cousteau Society. Center for Wetlands and Water Resources, University of Florida, Gainesville, FL. 60 pp.

Odum, H.T.: 1994, Ecological and General Systems. University Press of Colorado, Niwot, CO. 644 pp. (reprint of Systems Ecology, John Wiley, 1983)

Odum, H.T.: 1996, Environmental Accounting: Emergy and Environmental Decision Making; John Wiley and Sons, NY.

Odum, H.T. and J. E. Arding, 1991. Emergy Analysis of Shrimp Mariculture in Ecuador. Working Paper. Prepared for the Coastal Resource Center, University of Rhode Island, by Dept. Environmental Engineering Sciences and Center for Wetlands, University of Florida, Gainesville, FL. 114 pp.

Preliminary project work - to be completed during free time between sessions

Task One: Begin familiarizing yourself with state

  1. Locate detailed topographical map (check out USGS web site and state environmental protection agencies or divisions of natural resources). Determine major water inputs and outlets. List major ecosystems present.
  2. Conduct internet search for potentially relevant environmental, economic and social issues and historical background.
  3. Determine key industries and major company names, noting addresses for obtaining annual reports.
  4. Conduct internet and literature search for contact information for important government offices that will have data necessary for evaluation and other possible economic and environmental data sources - water boards, tourist commissions, electricity co-ops and agricultural departments, refereed journals, statistical abstracts, EPA superfund and watershed web sites for example.
  5. Draw a detailed systems diagram of important components and interactions.

Task Two: Begin outline for work to be completed

  1. Begin spreadsheet setup for evaluation, including all components you think should be evaluated based on preliminary information gathered in Task 1 and other evaluations studied using your diagram and the template provided.
  2. Locate relevant energy and material conversion factors and physical formulas for items listed - converting BTUs to joules for natural gas production or Langleys to J/m2/yr for example. Put these in the notes for each item.
  3. Look for transformities for all items listed - list source and a brief description of study parameters (eg: Folio 4, tomato produced on traditional central Florida agribusiness farm, or Lagerberg, tomato produced in Swedish agribusiness hothouse). Put these in the notes for each item.
  4. Make a list of transformities and conversions you could not locate after checking references provided.

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