Coal, a nonrenewable fossil fuel, accounts for nearly half of all electricity produced in the United States. We monetized effects associated with emissions from 406 coal-fired power plants, excluding Alaska and Hawaii, during 2005. These facilities represented 95% of the country’s electricity from coal. Although coal-fired electricity generation from the 406 sources resulted in large amounts of pollution overall, a plant-by-plant breakdown showed that the bulk of the damages were from a relatively small number of them. In other words, specific comparisons showed that the source-and-effect landscape was more complicated than the averages would suggest.
Damages Unrelated to Climate Change The aggregate damages associated with emissions of SO2, NOx, and PM from these coal-fired facilities in 2005 were approximately $62 billion, or $156 million on average per plant.4 However, the differences among plants were wide—the 5th and 95th percentiles of the distribution were $8.7 million and $575 million, respectively. After ranking all the plants according to their damages, we found that the 50% of plants with the lowest damages together produced 25% of the net generation of electricity but accounted for only 12% of the damages. On the other hand, the 10% of plants with the highest damages, which also produced 25% of net generation, accounted for 43% of the damages. Figure S-1 shows the distribution of damages among coal-fired plants.
Some of the variation in damages among plants occurred because those that generated more electricity tended to produce greater damages; hence, we also reported damages per kilowatt hour (kWh) of electricity produced. If plants are weighted by the amount of electricity they generate, the mean damage is 3.2 cents per kWh. For the plants examined, variation in damages per kWh is primarily due to variation in pollution intensity (emissions per kWh) among plants, rather than variation in damages per ton of pollutant. Variations in emissions per kWh mainly reflected the sulfur content of the coal burned; the adoption, or not, of control technologies (such as scrubbers); and the vintage of the plant—newer plants were subject to more stringent pollution-control requirements. As a result, the distribution of damages per kWh was highly skewed: There were many coal-fired power plants with modest damages per kWh as well as a small number of plants with large damages. The 5th percentile of damages per kWh is less than half a cent, and the 95th percentile of damages is over 12 cents.5
The estimated air-pollution damages associated with electricity generation from coal in 2030 will depend on many factors. For example, damages