Injection / Withdrawal Transmission Cost Allocation Updated Slides OMS CARP Group November 19, 2009

2 Current Att. O Transmission Revenue Requirements by Pricing Zone and Voltage Level Source: FERC Docket ER filed August 1, 2007, except for MEC and MPW who were not members at this date. MEC submitted the stated percents and MPW assumed to have similar break-down as CWLP and CWLD. ATC has also submitted updated percentages. Note: 2009 Att. O Revenue Requirements includes Account External Transaction Revenue Replacement for Slide 87

3 Scenario 4: Engineering Analysis Scenario

4 Difference in Load and Generation Charges by Pricing Zone Scenario 4: Engineering Analysis for All Revenue vs. Scenario 1: Engineering Analysis except Att. O Local Replacement for Slide 108

5 Difference in Total Charges to Load by Pricing Zone Scenario 4: Engineering Analysis for All Revenue vs. Scenario 1: Engineering Analysis except Att. O Local Replacement for Slide 109

6 Difference in Total Charges to Load by State Scenario 4: Engineering Analysis for All Revenue vs. Scenario 1: Engineering Analysis except Att. O Local Replacement for Slide 110

7 $/MWh Difference in Total Charges to Load by Pricing Zone Scenario 4: Engineering Analysis for All Revenue vs. Scenario 1: Engineering Analysis except Att. O Local Replacement for Slide 111

8 $/MWh Difference in Total Charges to Load by State Scenario 4: Engineering Analysis for All Revenue vs. Scenario 1: Engineering Analysis except Att. O Local Replacement for Slide 112

9 Estimated State Percentage Retail Rate Impact Scenario 4: Engineering Analysis for All Revenue vs. Scenario 1: Engineering Analysis except Att. O Local Replacement for Slide 113