1 / 27

Resource Flow Analysis

Resource Flow Analysis. ScottMatthews 12-712 / 19-622 Lecture 8. Administrative Issues. HW 3 Graded (avg 45) HW 4 Due Wednesday Project Updates Only 5 groups submitted plans last week. Recap of Last Time. Ecological footprint Relevant metric (equiv land use)

Download Presentation

Resource Flow Analysis

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Resource Flow Analysis ScottMatthews 12-712 / 19-622 Lecture 8

  2. Administrative Issues • HW 3 Graded (avg 45) • HW 4 Due Wednesday • Project Updates • Only 5 groups submitted plans last week

  3. Recap of Last Time • Ecological footprint • Relevant metric (equiv land use) • Concerns/issues about data and assumptions • Gallery show

  4. Mass Balance • Fundamental principle of engineering / environmental engineering (law of conservation of mass) • Commoner: “everything must go somewhere” • Physical quantities • Energy • Calories, etc. • Relevant: stocks and flows, ins and outs

  5. Source: USGS

  6. Material (Resource) Flow Analysis • Has existed for 100 years, but formalized as a modeling technique more recently • Tool to link impacts with material uses • Simple: materials book-keeping • Complex: dynamic flow analyses • Inevitably an IN=OUT issue • Is this trivial? Is it relevant? Do others realize? • We tend to underestimate complexity – i.e. simple materials in fact very complex flows

  7. MFA – Definition (Brunner) • A systematic assessment of stocks and flows of a material at a given space/time • Connects sources and pathways with sinks, intermediate flows

  8. Basic Plan for an MFA • Begin building a simple IN=OUT model • Start assembling IN, OUT flow data • Are there many more relevant IN, OUT flows? • Is there a substantial stock or sink? • Do we have sufficient data to quantify them? • Continue iterating as data and time allow • When done, summarize as many disaggregate stocks and flows as possible • Typically express results “over life cycle”

  9. Source: Brunner

  10. Source: USGS “MFA and Sustainability”

  11. Source: Yale STAF Project

  12. Cadmium USGS Report

  13. Postel (1996) - Water

  14. Computers • What Data do we have? • What data do we need? • Can we do a “good enough” job?

  15. Group exercise • Split into groups • Try to do computer MFA for 2008

  16. Source: USGS, Obsolete Computers, “Gold Mine,” or High-Tech Trash? Resource Recovery from Recycling

  17. Policy Relevance of MFA • Can we track natural versus anthropogenic flows? • JIE paper – Cadmium – only way to reduce is to eliminate inflow • But inflow is byproduct of Zinc; either need to eliminate zinc production or cut off co-product • Structure of such studies – and construction of the stock/flow models – yields insights • Can we learn more about connections between stocks and flows, our activities?

  18. MFA Issues • Data / methods are largest barriers (conceptually simple otherwise) • What about uncertainty?

  19. Sankey Diagrams • Generally used for Energy flow analyses • Implicit assumptions • The diagrams concern quantity sizes that are related to a period in time or to a functional unit, such as a product unit. • The quantity scale is proportional (i.e., twice the quantity is represented by an arrow that is twice as wide). • Inventories are not taken into account (i.e., there is no stock formation). • An energy or mass balance is maintained.

  20. Source: WRI, http://www.wri.org/image/view/9529/_original

  21. Lead Flows 1970 (USGS)

  22. Lead Flows 1993

  23. To Dos • HW 5 coming Wednesday. • Start tracking your expenses AND your general “material/resource” flow starting tomorrow am. Will need to for HW.

More Related