Page 111 - Design for Environment A Guide to Sustainable Product Development

90 Cha pte r Six

1. Designers need to strive to ensure that all material and energy
inputs and outputs are as inherently nonhazardous as possible.
2. It is better to prevent waste than to treat or clean up waste after
it is formed.
3. Separation and purification operations should be designed to
minimize energy consumption and materials use.
4. Products, processes, and systems should be designed to maxi-
mize mass, energy, space, and time efficiency.
5. Products, processes, and systems should be “output pulled”
rather than “input pushed” through the use of energy and
materials.
6. Embedded entropy and complexity must be viewed as an
investment when making design choices on recycle, reuse, or
beneficial disposition.
7. Targeted durability, not immortality, should be a design goal.
8. Design for unnecessary capacity or capability (e.g., “one size fits
all”) solutions should be considered a design flaw.
9. Material diversity in multicomponent products should be
minimized to promote disassembly and value retention.
10. Design of products, processes, and systems must include
integration and interconnectivity with available energy and
materials flows.
11. Products, processes, and systems should be designed for
performance in a commercial “afterlife.”
12. Material and energy inputs should be renewable rather than
depleting.

TABLE 6.2 Twelve Principles of Green Engineering [3]

2. Design for Detoxification—Minimize the potential for ad -
verse human or ecological effects at every stage of the life
cycle. This can be achieved through replacement of toxic
or hazardous materials with benign ones; introduction of
cleaner technologies that reduce harmful wastes and emis-
sions, in cluding greenhouse gases; or waste modification
using chemical, energetic, or biological treatment. Note that,
while detoxification can reduce environmental impacts, it may
not substantially reduce resource consumption.
3. Design for Revalorization—Recover residual value from
materials and resources that have already been utilized in the
economy, thus reducing the need for extraction of virgin
resources. This can be achieved by finding secondary uses for