Lecture 20 Life-cycle Analysis

Gang He

November 16, 2023

Sample analytic questions

  • How to compare the emissions of energy technology fairly?
  • Does EV reduces or increase emissions?
  • Does CO2 enhanced oil recovery reduces carbon emission?
  • GHG implications of biomass?

LCA questions

  • Paper or plastic grocery bags
  • Cloth or disposable diapers
  • Digital or hardcopy papers/books
  • Plastic water bottles or tap water

System thinking

  • Acknowledging the complex connectivity of our societies, economies and the natural environment
  • Understanding system behaviors and responses (positive and negative)
  • Modifying complex systems to achieve a more sustainable balance
  • Life cycle thinking, applied to products and processes, is a specific example of systems thinking

LCA

The assessment of environmental impacts of products or processes from “cradle to grave”

“Cradle to Grave”
- Raw material extraction
- Manufacturing
- Transportation
- Usage
- Disposal

Environmental impacts
- Greenhouse gases
- Particulates
- Water withdrawal
- Toxics
- Land use

LCA Thinking

LCA of Real vs Fake Christmas Tree

Another thought experiment

How should drinks be provided?
- 12 oz. aluminum (soda) cans
- 12 oz. steel (soda) cans
- 2 liter plastic (soda) bottles
- 8 oz. (fresh juice) boxes
- 32 oz. paperboard (fresh juice) boxes
- 8 oz. paperboard (concentrated and frozen juice) cans
- 10 oz. refillable glass bottles (from the 1970s)
- Syrup concentrate (from fountain machines)

History of LCA

Initial LCA work was focused on energy

1969 - first multi-criteria study for Coca-Cola
- Glass versus plastic for container
- Choice between internal / external container production
- End of life options (recycling or one-way)
- Result: plastic bottle was better, contrary to expectations
- Study never published
- Questions of validity then occurred
- Led to calls by scientific community for a standardization process

The 80’s: LCA as a marketing instrument

LCA was used in the marketing claims

In 1991, the USA denounced the use of LCA results until further standards were in place.

1997: ISO 14000 Standardization

ISO 14000 Standards of Environmental Management
ISO 14001 Certification of Environmental Management Systems
ISO 14010 Audit guidelines
ISO 14011 Audit methodology
ISO 14012 Qualification of auditors
ISO 14013-14015 Audit processes
ISO 14020-14025 Environmental labeling
ISO 14031-14032 Environmental performance evaluation
ISO 14040 / 14044 Life Cycle Assessment – General principles and practices
ISO 14050 Terms and Definitions
ISO 19011 Guide for management systems auditing

Rationale for a standard

  • Want things done consistently
    • Common guidelines
  • Want to set level playing field in a market
    • Following the standard is assessable, and determined compliant
  • Analogous to ASTM and other “test standards”
    • e.g., consistent concrete is desired and can be specified in a construction bid request: “we want ASTM C94 concrete”
    • LEED Green Building Standards family
  • Standards generally voluntary, but may be required by contract (require ISO 9000 compliant firm)

Standard oganization

  • Scope
  • Normative references
  • Terms and definitions
  • General description of LCA
    • Principles; Phases; Key features; General concepts of product systems
  • Methodological framework
  • Reporting
  • Critical review

Phase of an LCA

Recall renewables save water

What LCA is what’s not

  • LCA is a way of structuring/organizing the relevant parts of the life cycle
  • It is a tool to track performance
  • LCA is not a cure-all for our environmental problems
  • LCA is not an “exact” science with provable axioms/theories
  • LCA is part of the sustainability tool box

Uncertainties in LCA

  • Use care in using simplistic methods to support decisions
  • “A decision made without taking uncertainty into account is barely worth calling a decision.” (Wilson, 1985)
  • Presumed focus of book and course
  • We’re doing LCA for big decisions
    • Hybrid cars? Green energy? Change-the-world policy questions
  • Thus analysis should be as good as possible
  • “It depends” studies perhaps just not “complete” studies
  • LCA is a robust methodology that requires careful choice of methods and leverage of quantitative tools.

Summary

  • System thinking and LCA thinking
  • LCA could offer insights
  • Learning those new tools and skills to do basic LCA
  • LCA is a system think to address energy and climate challenges.

References

IEA. 2016. “Water Energy Nexus Excerpt from the World Energy Outlook 2016.” https://www.iea.org/reports/water-energy-nexus.
Meadows, Donella H. 2008. Thinking in Systems: International Bestseller. Edited by Diana Wright. White River Junction, Vt: Chelsea Green Publishing.