Air Pollution - Environmental Science - page 363

Ultimately, the success of any emissions trading
approach depends on how low the initial cap is set and
then on how much it is reduced annually to promote
continuing innovation in air pollution prevention and
control. Without these elements, emissions trading
programs mostly move air pollutants from one area to
another without achieving any overall reduction in air
quality.
Good news. Between 1990 and 2002, the emissions
trading system helped reduce SO 2 emissions from
electric power plants in the United States by 35%. The
cost of doing so amounted to less than one-tenth of the
cost projected by industry, because the market-based
system motivated companies to reduce emissions in
more efficient ways.
The EPA has also created an emissions trading pro-
gram for smog-forming nitrogen oxides in a number of
states in the East and Midwest. Emissions trading may
also be implemented for particulate emissions and
VOCs and for the combined emissions of SO 2 ,NO x , and
mercury from coal-burning power plants. Environ-
mental and health scientists are particularly opposed to
using a cap-and-trade program to control emissions of
mercury by coal-burning power plants and industries
because this pollutant is highly toxic, falls out of the at-
mosphere adjacent to such facilities, and does not break
down in the environment. Coal-burning plants choos-
ing to buy permits instead of sharply reducing their
mercury emissions would create toxic hot spots with
unacceptably high levels of mercury.
Bad news. In 2002, the EPA reported results from
the country's oldest and largest emissions trading pro-
gram, in effect since 1993 in southern California.
According to the EPA, this cap-and-trade model “pro-
duced far less emissions reductions than were either
projected for the program or could have been expected
from” the command-and-control system it replaced.
The same study also found accounting abuses, includ-
ing emissions caps set 60% higher than current emis-
sions levels. This highlights the need for more careful
monitoring of all cap-and-trade programs.

Solutions

Stationary Source Air Pollution

Prevention Dispersion or

Cleanup

Burn low-sulfur coal Disperse emissions

above thermal
inversion layer with
tall smokestacks Remove sulfur

from coal

Convert coal to a
liquid or gaseous
fuel

Remove pollutants
after combustion

Shift to less
polluting fuels

Tax each unit of
pollution produced

Figure 15-17 Solutions: methods for reducing emissions of
sulfur oxides, nitrogen oxides, and particulate matter from sta-
tionary sources such as coal-burning electric power plants and
industrial plants. Critical thinking: which two of these solutions
do you believe are the most important?

Approximately 20,000 older coal-burning plants,
industrial plants, and oil refineries in the United States
have not been required to meet the air pollution stan-
dards required for new facilities under the Clean Air
Acts. Environmentalists and officials of states subject
to pollution from such plants have been trying to get
Congress reverse this situation since 1970. To date,
they have been not been successful because of strong
lobbying efforts by U.S. coal and oil industries.
In 2004, Abt Associates, a consulting firm hired
by the EPA, estimated that air pollution from the na-
tion's 1,100 largest coal-fired power plants causes
24,000 premature deaths, 38,200 nonfatal heart at-
tacks, 554,000 asthma attacks, and 3 million lost work-
days each year. Approximately 90% of these deaths
could be prevented by rigid enforcement of the exist-
ing Clean Air Acts and by requiring older coal-burn-
ing plants to install currently available air-pollution
control technology systems.
Figure 15-18 (p. 364) lists ways to reduce emis-
sions from motor vehicles, the primary culprits in pro-
ducing photochemical smog.
Good news. Over the next 10-20 years, air pollution
from motor vehicles should decrease from increased
use of partial zero-emission vehicles (PZEVs ) that emit
almost no air pollutants thanks to their improved en-
gine and emission systems, hybrid-electric vehicles (Fig-
ure 13-24, p. 309), and vehicles powered by fuel cells
running on hydrogen (Figure 13-25, p. 310).

x

H OW W OULD Y OU V OTE ? Should emissions trading be
used as the primary way to control emissions of all major air
pollutants? Cast your vote online at http://biology.brookscole
.com/miller11.

Solutions: Reducing Outdoor
Air Pollution
There are a number of ways to prevent and control air
pollution from coal-burning facilities and motor
vehicles.
Figure 15-17 summarizes ways to reduce emissions of
sulfur oxides, nitrogen oxides, and particulate matter
from stationary sources such as electric power plants
and industrial plants that burn coal.