12 Principles of Green Engineering

Green engineering is defined by 12 principles, or methodologies, that can be applied to develop sustainable technologies.

  1. Inherent Rather than Circumstantial: Designers need to strive to ensure that all materials and energy inputs and outputs are as inherently nonhazardous as possible.
  2. Prevention Instead of Treatment: It is better to prevent waste than to treat or clean up waste after it is formed.
  3. Design for Separation: Separation and purification operations should be designed to minimize energy consumption and materials use.
  4. Maximize Efficiency: Products, processes and systems should be designed to maximize mass, energy, space, and time efficiency.
  5. Output-Pulled Versus Input-Pushed: Products, processes, and systems should be "output pulled" rather than "input pushed" through the use of energy and materials.
  6. Conserve Complexity: Embedded entropy and complexity must be viewed as an investment when making design choices on recycle, reuse, or beneficial disposition.
  7. Durability Rather than Immortality: Targeted durability, not immortality, should be a design goal.
  8. Meet Need, Minimize Excess: Design for unnecessary capacity or capability (e.g., "one size fits all") solutions should be considered a design flaw.
  9. Minimize Material Diversity: Material diversity in multicomponent products should be minimized to promote disassembly and value retention.
  10. Integrate Material & Energy Flows: Design of products, processes, and systems must include integration and interconnectivity with available energy and materials flows.
  11. Design for Commercial “Afterlife”: Products, processes, and systems should be designed for performance in a commercial "afterlife."
  12. Renewable Rather than Depleting: Material and energy inputs should be renewable rather than depleting.