Page 348 - Design for Environment A Guide to Sustainable Product Development

CHAPTER 18

Energy Production

Industries

Overview
Sustainable energy production is, quite simply, the paramount chal-
lenge facing the global economy. World petroleum reserves are
dwindling, and the unprecedented spike in oil prices during 2008—
approaching $150 per barrel—was a warning signal to global manu-
facturers dependent on petroleum fuel for supply chain operations.
In the United States, which imports the majority of its oil from abroad,
there has been an increasing cry for “energy independence.” How-
ever, weaning any industrial economy away from petroleum will not
be easy. Renewable sources of biofuels, such as corn-based and cel-
lulosic ethanols, are less efficient than gasoline, and are challenged by
the life-cycle environmental burdens of harvesting the biomass. Plug-
in hybrids are a viable alternative; but electric power is still largely
generated by coal, which is confronted with its own environmental
challenges, while nuclear power is still controversial.
From a broad sustainability perspective, it is generally accepted
that we must drastically reduce global greenhouse gas emissions in
order to stabilize atmospheric levels of carbon. Yet, as shown in Figure
18.1, the U.S. economy remains heavily dependent on nonrenewable
fossil fuels, which continue to account for about 85% of domestic
energy use. Nuclear energy accounts for about 8%, and approximately
6% is derived from renewable sources [1]. The worldwide average
consumption data are very similar, and these numbers have not
changed appreciably for about a decade.
On a positive note, the greenhouse gas intensity (metric tons per
$million) of the U.S. economy has fallen significantly from 1990 to
2005, as shown in Figure 18.2. However, this decrease resulted mainly
from increased efficiency in industrial and commercial energy use
rather than increased use of low-carbon fuels. The reduced GHG
intensity was offset by economic growth, resulting in about a 17%
overall increase in GHG emissions during that period. It appears that

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