Geoscience Reference
In-Depth Information
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Coal
Petroleum
Natural gas
Figure 24.
A projection of the most eco nom ical way for the United States to reduce
CO
2
emissions by fuel type. According to a study by the U.S. Energy Information
Administration, we should reduce coal use most sharply. These results are similar to
those of other economic models.
This leads to one further point. The costs involved in reducing CO
2
emissions are potentially very large. Signifi cant reductions in emissions
cannot be done easily, quickly, or cheaply with today's technologies or
those that are ready for large-scale deployment. It will require consider-
able ingenuity to craft inexpensive ways to reduce emissions. Yet we need
to ensure that societies rely on the least expensive approaches. Returning
to our examples of refrigerators versus electricity generation, we saw a
cost difference of a factor of almost ten. When we are talking about re-
ducing emissions by billions of tons, the economic stakes are enormous.
THE AGGREGATE COST-REDUCTION CURVE
The discussion above illustrated CO
2
cost reductions using typical
decisions such as the choice of refrigerators for households and power
plants for electric utilities. But ultimately we are interested in the cost
for the entire economy. Experts have studied the CO
2
cost reduction
