Environmental Engineering Reference
In-Depth Information
to what is now a jumble of different approaches, but it
is not likely we will see one soon. Here I will describe
the approaches being discussed nationally and give my
evaluation of some good and bad policies with my score-
card at the end.
.
Reducing Emissions on
a National Scale
There are two large-scale options under discussion. One
is called Cap and Trade, while the other is called a carbon
tax by most but I prefer to call it an emissions fee. Both
alternatives seek to move the country away from its pre-
sent dependence on fossil fuels though in different ways.
Cap and Trade had the political lead in
after the
election of President Obama.
Cap and Trade is proposed as an economically ef
cient
way of reducing pollutants. It was
first tried in the United
States in an effective move to curtail acid rain by regulat-
ing and reducing sulfur dioxide (SO
) emissions from
coal-
red power plants (SO
mixes with water vapor in
the atmosphere to form sulfuric acid; hence acid rain).
Here is a simpli
ed version of how such a system works.
Each plant receives an allowance to emit a certain amount
of SO
for some period of time, a year, for example. The
total number of allowances is equal to the total emissions
of all plants. For the next period the total allowance is cut
by reducing the allowance for each plant by the same
percentage as the total is reduced. A particular plant can
switch to a cleaner fuel thereby emitting less, install
equipment to catch the SO
before it gets out, buy extra
allowances from other plants that can meet their required
