1. 1 Grid Impact of PEV Charging Possible Consequences Jan Berman Sr. Director, Policy & Integrated Planning Integrated Demand Side Management Customer Care 06 August 2010

2. 2 PEV Charging Creates a Significant Increase In Load Customers will prefer a 240V charge to shorten recharge times PEV charging is a large load for PG&E customers, comparable to average peak summer load of a single home 240V/30A 4 hours 240V/15A 8 hours 120V/12A Rate of charge BEV Recharge time 16 hours

3. 3 The Existing Grid Substation Customer Generation Transmission Customer Switching Device

4. 4 Scenario 1: Two PEVs in Berkeley, Two Circuits Substation Customer Transmission Customer Generation Switching Device

5. 5 Scenario 2: Two PEVs in Berkeley - Single Circuit Substation Customer Transmission Customer Generation Switching Device

6. 6 Zip code level Specific Notification Drives Proper Upgrade Planning Substation Customer Transmission Customer Address level Switching Device Generation

7. 7 24 Hour Total Loading of Single Feeder - July 27, 2007 4000 5000 6000 7000 8000 9000 10000 11000 12000 01234567891011121314151617181920212223 Hours Total Loading at Substation (KW) Base Load Scenario (no PHEV) Case 1:- Do nothing (charge @6pm) Case 2:- TOU rates only (charge @9pm) Case 3:- TOU rates and Smart Charging (charge @9pm-1am) When most customers arrive home off-peak load Left Unmanaged, PEV Load Will Add to Peak Electric Demand Source: EPRI. Note: Feeder of Northeastern utility feeder during urban summer peak with 2,778 residential customers. PEV penetration = 10%. Case 1 – 3 charge @ 240V, 12A

8. 8 Bay Area EV Adoption and Load Forecasts Correlate Cities with most hybrids per zip code PG&E EV Load Forecast Nissan Leaf Reservations * Hybrid registrations from 2004 to 2008, source: Polk & Co. 2007 Outage Density (# of outages per distribution transformer)

9. 9 PG&E is Committed to PEVs

10. 10 Thank You Contact: jsb1@pge.com