1. Emission Levels, Reference Case Projections for 2010 and 2020, and Target Caps for Electricity Generators 199720102020Target 0 2,000 4,000 6,000 8,000 Thousand Tons per Year Nitrogen Oxides 6191 4340 4480 1548 1997 20102020Target 0 4,000 8,000 12,000 16,000 Thousand Tons per Year Sulfur Dioxide 13090 9700 8950 2240 199020102020Target 0 200 400 600 800 Million MetricTons Carbon Equivalent per Year Carbon Dioxide 475 691 773 475 199920102020Target 0 15 30 45 60 Tons per Year Mercury 43 46 45 4.3

2. Electricity Prices With and Without Emissions Limits, 1990-2020 (1999 cents per kilowatthour) 0 2 4 6 8 10 199019992005201020152020 Without Emissions Limits With Emissions Limits

3. 199019992005201020152020 0 1 2 3 4 Without Emissions Limits With Emissions Limits Natural Gas Wellhead Prices With and Without Emissions Limits, 1990-2020 (1999 dollars per thousand cubic feet)

4. Emission Allowance Prices in the Reference Case With Emissions Limits, 2020 Mercury in 1999 dollars per pound Sulfur Dioxide, Nitrogen Oxides, and Carbon Dioxide in 1999 dollars per ton Sulfur Dioxide Nitrogen Oxides Carbon Dioxide 0 50,000 100,000 150,000 200,000 Mercury 153,000 0 200 400 221 122 0

5. 0 500 1,000 1,500 -500 -1,000 -1,500 Coal Natural Gas Renewable Nuclear Electricity Demand Change in Coal vs. Natural Gas, Renewable, and Nuclear Generation and Electricity Demand, 2020 (billion kilowatthours)

6. Unscrubbed Coal Plant Without SCRScrubbed Coal Plant With SCR 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 Sulfur Dioxide Carbon Dioxide Mercury Impact of 2010 Allowance Prices on Coal Plant Operating Costs (1999 cents per kilowatthour)