Page 349 - Design for Environment A Guide to Sustainable Product Development

324 Cha pte r Ei g h tee n

FIGURE 18.1 U.S. energy consumption by energy source in 2007 [1].

the only practical way to combat the global warming threat is to
increase the proportion of energy supplied by low-carbon energy
sources—renewable, nuclear power, and coal-fired plants with car-
bon capture—and thus decouple carbon emissions from economic
value creation.
What is the outlook for renewables? Most projections agree that,
even under optimistic investment scenarios, neither biofuels nor re -
newable electric power sources such as solar, wind, and geothermal

FIGURE 18.2 Growth of U.S. greenhouse gas emissions, 1990–2005, and
change in intensity [1].