Visualizing Environmental Science

Oil and Natural Gas 423

Will & Deni McIntyre/©Corbis

oxides and removes sulfur from

the coal. It produces more heat

from a given amount of coal,

thereby somewhat reducing CO 2

emissions per unit of electricity

produced.

In the United States, several

large power plants are testing flu-

idized-bed combustion, and a few

small plants are already using this technology. The Clean

Air Act Amendments of 1990 provide incentives for utility

companies to convert to clean coal technologies. A few

coal-fired power plants are currently experimenting with

technologies that capture CO 2 before it can be emitted.

1. Why does surface mining of coal typically cause
   more environmental harm than does subsurface
   mining?


2. What are the environmental impacts of mining
   and burning coal?


3. What technologies can make coal a cleaner fuel?

Dead trees enveloped in acid fog on Mount
ˆÌV…i]Ê œÀ̅Ê

Àœˆ˜>ÊUʈ}ÕÀiʣǰÈÊ

Forest decline was first documented in Germany and eastern
Europe. More recently, it has been observed in eastern North
America, particularly at higher elevations. Acid deposition
contributes to forest decline.

1. Describe existing reserves of oil and natural gas.


2. Discuss the environmental problems caused by
   using oil and natural gas.

O

il and natural gas supplied approximately
62 percent of the energy used in the United
States in 2010. In comparison, other U.S.
energy sources include coal (21 percent),
nuclear power (9 percent), renewables (7 percent)
and liquid biofuels (1 percent). Globally, oil and natu-
ral gas provided 56 percent of the world’s energy
(ˆ}ÕÀiʣǰÇ).
Petroleum and natural gas originated when small
organisms settled to the ocean floor millions of years
ago. These organisms were buried under silt, and over
long periods of time were subjected to pressure and
temperature, altering their chemical makeup. Petro-
leum, or crude oil, is a liquid composed of hundreds of

Oil and Natural Gas

LEARNING OBJECTIVES

fluidized-bed

combustion

A clean-coal

technology in which

crushed coal is mixed

with limestone to

neutralize acidic

compounds produced

during combustion.

Oil Coal Renew-

ables

Natural Nuclear

gas

40

30

20

10

Percentage of world commercial energy 0

production, 2010

Based on data from the Energy Information Administra-tion (EIA).

World commercial energy

ÜÕÀViÃÊUʈ}ÕÀiʣǰÇÊ

Note the overwhelming reliance on oil, coal, and natural gas as

commercial energy sources. “Alternatives” include geothermal,

solar, wind, and wood electric power.

Several advanced technologies allow power plants
to produce less air pollution while burning coal. In
fluidized-bed combustion, crushed coal is mixed with
limestone particles in a strong air current during
combustion. This technology produces fewer nitrogen

Interpreting Data

There are currently 435 nuclear power plants operating

worldwide. How many additional nuclear plants would be

needed for the world to produce as much commercial en-

ergy using nuclear power as we currently do using coal?