Energy - Environmental Science - page 288

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Science and Politics: Energy Future
of the United States
There is debate over whether U.S. energy policy
for this century should maintain the country's
dependence on oil and coal or focus more on
natural gas, hydrogen, and solar cells.
The United States is the world's largest energy user.
The average American consumes as much energy in
one day as a person in the poorest country consumes
in a year. In 2005, with only 4.6% of the world's popu-
lation, the United States used almost one-fourth of the
world's commercial energy. In contrast, India, with
16% of the world's people, used 3% of the world's
commercial energy.
About 93% of the commercial energy used in the
United States comes from nonrenewable energy re-
sources—85% from fossil fuels and 8% from nuclear
power (Figure 13-3, right). The remaining 6% comes
mostly from renewable biomass and hydropower.
An important environmental, economic, and po-
litical issue is the energy resources that the United
States might be using by 2050 and 2100. Figure 13-4
shows the shifts in use of commercial sources of en-
ergy in the United States since 1800, and one scenario
projecting changes to a solar-hydrogen economy by
2100. According to the U.S. Department of Energy
(DOE) and the Environmental Protection Agency
(EPA), burning fossil fuels causes more than 80% of
U.S. air pollution and 80% of U.S. carbon dioxide emis-
sions. Many energy experts contend that the need to
use cleaner and less climate-disrupting (noncarbon)
energy resources—not the depletion of fossil fuels—
will be the driving force behind the projected transi-
tion to a solar-hydrogen energy age in both the United
States and other parts of the world during this century.
Whether the shift shown in Figure 13-4, or some
other scenario, occurs depends primarily on which
energy resources the U.S. government decides to pro-
mote as matters of policy. If we want energy alternatives
such as solar energy and hydrogen to become main
dishes instead of side orders on our energy menu, they
must be nurtured by government subsidies and tax
breaks.
The fossil fuel and nuclear power industries that
have been receiving large government subsidies for
more than 50 years understandably do not want to
give them up. They will exert their considerable politi-
cal muscle to keep these subsidies, even though they
are mature and profitable industries that do not need
such nurturing.
Thus the energy path taken by the United States
(or any country) is primarily a political decision made
by elected officials with pressure from officials of
energy companies and from citizens. As a citizen, you
can play an important role in deciding the energy fu-

Wood

Coal

80

Natural gas

60

Oil

?

40

Hydrogen
Solar

20

Nuclear

0

1800 1875 1950 2025 2100

Year

Figure 13-4 Shifts in the use of commercial energy resources in
the United States since 1800, with projected changes to 2100.
Shifts from wood to coal, and then from coal to oil and natural
gas, have each taken about 50 years. The projected shift to a
solar-hydrogen economy by 2100 is only one of many possible
scenarios. (Data from U.S. Department of Energy)

ture for yourself and for your children. Indeed, this
decision is one of the most important political acts you can
undertake.

Science and Economics: Deciding Which
Energy Resources to Use
We need to answer several questions in deciding
which energy resources to promote.
Energy policies need to be developed with the future
in mind because experience shows that it usually takes
at least 50 years and huge investments to phase in new
energy alternatives to the point where they provide
10-20% of total energy use. Making projections such as
those in Figure 13-4 and then converting such projec-
tions to energy policy involves trying to answer the
following questions for each energy alternative:

■ How much of the energy resource is likely to be
available in the near future (the next 15-25 years) and
the long term (the next 25-50 years)?
■ What is the net energy yield for the resource?
■ How much will it cost to develop, phase in, and
use the resource?
■ What government research and development sub-
sidies and tax breaks will be used to help develop the
resource?
■ How will dependence on the resource affect na-
tional and global economic and military security?
■ How vulnerable is the resource to terrorism?
■ How will extracting, transporting, and using the
resource affect the environment, human health, and
the earth's climate? Should these harmful costs be in-
cluded in the market price of each energy resource