varied widely. The lowest-damage 50% of plants, which accounted for 25% of net generation, produced 12% of damages, and the highest-damage 10% of plants, which also accounted for 25% of net generation, produced 43% of the damages. Although damages are larger for plants that produce more electricity, less than half of the variation in damages across plants is explained by differences in net generation.
Damages per kWh also varied widely across plants: from approximately half a cent (5th percentile) to over 13 cents per kWh (95th percentile). (These are unweighted figures.) Most of the variation in damages per kWh can be explained by variation in emissions intensity across plants. In the case of SO2, which accounts for 85% of the damages associated with SO2, NOx and PM, over 80% of the variation in SO2 damages per kWh is explained by variation in pounds of SO2 emitted per kWh. Damages per ton of SO2 emitted, which vary with plant location, are less important in explaining variation in SO2-related damages per kWh. (They are, by themselves capable of explaining only 24% of the variation in damages per kWh.)