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 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 The Existing Grid Substation Customer Generation Transmission Customer Switching Device

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

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

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

7 24 Hour Total Loading of Single Feeder - July 27, Hours Total Loading at Substation (KW) Base Load Scenario (no PHEV) Case 1:- Do nothing Case 2:- TOU rates only Case 3:- TOU rates and Smart Charging 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 240V, 12A

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 Outage Density (# of outages per distribution transformer)

9 PG&E is Committed to PEVs

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