1. Lou Oberski WEQ EC Chair Lou Oberski WEQ EC Chair THE ELECTRIC DAY Energy Day Meetings December 1-2, 2004 THE ELECTRIC DAY Energy Day Meetings December 1-2, 2004

2. The Standard Electric Day Midnight to Midnight - Changes with time zone - Market timelines may differ by region but are based on midnight to midnight in their respective time zone

3. The Standard Electric Day 24 Hour Operation On peak hours Monday thru Saturday Eastern Interconnection - - 7:00 a.m. to 11:00 p.m. EPT 6:00 a.m. to 10:00 p.m. CPT ERCOT - - 8:00 a.m. to 11:00 CPT Western Interconnection - - 7:00 a.m. to 11:00 p.m. PPT Off peak hours (includes all hours on Sundays and Holidays) Eastern Interconnection - - 11:00 p.m. to 7:00 a.m. EPT 10:00 p.m. to 6:00 a.m. CPT ERCOT - - 11:00 p.m. to 8:00 a.m. CPT Western Interconnection - - 11:00 p.m. to 7:00 a.m. PPT 7:00 a.m.11:00 p.m. Midnight to Midnight Electric Day On-Peak Energy Products

4. 7:00 a.m.11:00 p.m. Midnight to Midnight Electric Day On-Peak Energy Products - Most liquid on-peak 5x16 - 5 weekdays, 16 hrs/day - Contained within 1 electric day - Spans 2 current gas days

5. Accounting,Settlement & Balancing - Done hourly based on calendar day (electric day) - Electricity has an instantaneous supply and demand balance requirement - Electricity has no equivalent to gas storage - Voltage levels strictly regulated - Unable to change voltage the way gas changes pressure 7:00 a.m.11:00 p.m. Midnight to Midnight Electric Day On-Peak Energy Products

6. Conclusions - Midnight to Midnight Electric Day exists with time zone variations - Simple standardization across time zones will require changes - Electric industry is a 24 hour business with instantaneous balancing requirements