Page 26 - Design for Environment A Guide to Sustainable Product Development

Intr oduction 5

FIGURE 1.1 The hidden mountain of resource consumption.

year [4]. We never see most of that material because it is released to
the envi ronment in the form of trash, wastewater, and airborne
emissions—mainly carbon dioxide. Only about 5% finds its way to
the customer in the form of consumable products such as food, and
durable goods such as furniture. A small fraction is recycled, but the
rest is simply thrown away.
For example, assuming that an individual consumes 1 plastic
quart bottle per day, her annual consumption generates about 5 kg of
solid waste per year (11 lb). Recycling may reduce that total, although
it still requires resources to bring the bottles back to the point where
they reenter the manufacturing stream. However, if we consider the
resources—both energy and materials—required in the full life cycle
for those plastic bottles, including resource extraction, manufactur-
ing, and transportation, it requires a total of about 250 kg of materi-
als, 98% of which end up as solid waste. In addition, the supply chain
as so ciated with plastic bottle manufacturing requires about 20 liters
of water per bottle, or a total of about 230 million metric tons per
year, mainly due to thermo-electric power generation and crop irri-
gation [5].
Plastic bottles are not unusual in this respect. The processes in -
volved in manufacturing and supporting most products have signifi-
cant impacts on the environment, including the generation of waste,
the disruption of ecosystems, and the depletion of natural resources.
About 20 billion tons of industrial wastes are generated annually in
the United States, and over a third of these are hazardous wastes. As a
result, U.S. communities are rapidly filling up available landfill space.
In the European Union, where unused land is scarce, a number of
strict directives have been issued that require manufacturers to re cover
and recycle discarded products and packaging (see Chapter 3). But
still the mountain grows.
The sobering message is that our current patterns of industrial
development threaten to exceed the capacity of ecosystems in terms