Page 574 - Environment: The Science Behind the Stories

We have developed a range of alternatives to fossil fuels
(see Table 19.1, p. 539). Most of these energy sources are
renewable, and most have less impact on health and the envi-
ronment than oil, coal, or natural gas. At this time most remain Oil
more expensive than fossil fuels, at least in the short term and (36.5%)
when external costs (pp. 164, 183) are not included in market
prices. As technologies develop and as we invest in infrastruc- New renewables Natural gas
ture to better transmit power from renewable sources, prices (1.9%) (27.3%)
will come down further and help us transition toward these Hydropower
new energy sources. (2.8%)
Nuclear
Bioenergy (4.5%) Coal
(8.5%)
Nuclear power, bioenergy, and hydropower (18.3%)
are conventional alternatives

Three alternative energy sources are currently the most devel- (a) U.S. energy consumption, by source
oped and most widely used: nuclear power, hydroelectric power,
and energy from biomass. Each of these well-established
energy sources plays a substantial role in our energy and elec- Oil Coal Natural gas Bioenergy
tricity budgets today. We can therefore call nuclear power, 40 Hydropower Nuclear power
hydropower, and biomass energy (bioenergy) “conventional
alternatives” to fossil fuels. 30
Each of these three conventional energy alternatives are
generally considered to exert less environmental impact than Quadrillion BTU
fossil fuels, but more impact than the “new renewable” alter- 20
natives (Chapter 21). Yet as we will see, they each involve a
unique and complex mix of benefits and drawbacks. Nuclear
power is commonly considered a nonrenewable energy source, 10
and hydropower and bioenergy are generally described as
renewable, but the reality is more complicated. Each of these 0
energy sources is perhaps best viewed as an intermediate 1950 1960 1970 1980 1990 2000 2010
along a continuum of renewability. Year
(b) U.S. energy consumption, 1949–2012
Conventional alternatives provide FIGURE 20.2 Fossil fuels predominate in the United States.
much of our electricity Together, oil, natural gas, and coal account for 82% (a) of U.S.
energy consumption. Over the past 60 years (b), U.S. consumption
Fuelwood and other bioenergy sources provide 10% of the of fossil fuels has grown faster than that of bioenergy or hydro-
world’s energy, nuclear power provides about 6%, and hydro- power. Nuclear power grew considerably between 1970 and 2000.
power provides about 2%. The less established renewable Data from U.S. Energy Information Administration, 2013.
energy sources together account for less than 1% (see Figure
20.1a). Although their global contributions to our overall
energy supply are minor, alternatives to fossil fuels do contrib- budget. Today nuclear power, bioenergy, and hydropower
ute greatly to our generation of electricity. Nuclear energy and together provide Sweden with over 60% of its energy and vir-
hydropower together account for nearly 30% of the world’s tually all of its electricity.
electricity generation (see Figure 20.1b).
Energy consumption patterns in the United States CHAPTER 20 • CONVENTI ON AL ENERGY ALTERN ATIVES
(FIGURE 20.2a) are similar to those globally, except that the Nuclear Power
United States relies less on fuelwood and slightly more on fos-
sil fuels and nuclear power than most other countries. A graph Nuclear power occupies an odd and conflicted position in
showing trends in energy consumption in the United States our modern debate over energy. It is free of the air pollution
over the past 60 years (FIGURE 20.2b) reveals two things. First, produced by fossil fuel combustion, so it has long been put
conventional alternatives play minor yet substantial roles in forth as an environmentally friendly alternative to fossil
overall energy use. Second, use of conventional alternatives fuels, and it remains one of our most influential solutions
has been growing more slowly than use of fossil fuels. to climate change. Yet nuclear power’s great promise has
Sweden, however, has shown that it is possible for a been clouded by nuclear weaponry, the dilemma of radio-
wealthy and advanced economy to replace fossil fuels gradu- active waste disposal, and the long shadow of Chernobyl
ally with alternative sources while continuing to raise living and now Fukushima. As such, public safety concerns and
standards for its citizens. Since 1970, Sweden has decreased the costs of addressing them have constrained nuclear
its fossil fuel use from 81% to 38% of its national energy power’s spread. 573

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