1. SM
2012 Summer Readiness
Irvine City Council Briefing
May 8, 2012
EDISON INTERNATIONAL®

2. SM
2012 Summer Readiness Briefing
• Introduction
• CA Independent System Operator (CAISO)
Reliability Overview
• Mitigation Measures
– Transmission
– Generation
– Demand Response and Conservation
– Customer Communications
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3. SM
2012 Summer Readiness Briefing
• San Onofre units 2 and 3 are a critical part of meeting the region's
electricity needs and voltage levels, representing 2,220 MW of
generation
• Prospect of a summer without units 2 and 3 is a significant challenge
that SCE is doing contingency planning around, working with state
agencies
• SCE will complete all required inspections and tests prior to restarting
either unit at San Onofre and is committed to doing every task safely,
no matter how much time that takes.
• The company’s number one priority is, and always has been, the
health and safety of the public and its employees.
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4. Summer Readiness
Dennis Peters
California Independent System Operator
May 8, 2012
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5. Shaping the industry
The ISO, a nonprofit public benefit
corporation, maintains the constant
and reliable flow of electricity for
the health, safety and welfare of
consumers
How?
 Delivering electricity to 80% of
California consumers
 Facilitating fair and transparent
wholesale electricity market
 Performing comprehensive
transmission planning
 Clearing the way for clean, green
resources to access the grid
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6. Who oversees us?
We are governed by a governor appointed/
Senate confirmed Five Member Board
We are regulated by
FERC Federal Energy Regulatory Commission
We are compliant with
NERC North American Electric Reliability Corporation
We are part of
WECC Western Electricity Coordinating Council
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7. Overview of the area and summer reliability challenges
without the San Onofre nuclear power plant
• Los Angeles Basin and San
Diego areas must have local
generation to serve all
consumers
• The ISO already plans for the
outage of one San Onofre
generating unit
• ISO must plan for the major
contingencies where San
Diego loses eastern
transmission and the largest
generator
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8. San Diego and the Los Angeles Basin are at risk of
outages under required planning standards
San Diego Los Angeles Basin
Without both San Without both
Onofre units - San Onofre
Import capability Units – Total gen
Total gen +3048 Total gen +9418
Import capability +2100 Import capability +10,771*
Largest generation -603 Largest generation -498**
outage outage
Load -4882 Load -19,931
Reserve margin = -337 Shortfall = -240
Notes:
* Transmission import capability is subject to change, as
system conditions change from year to year.
**Largest generating unit outage after both San Onofre
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9. Actions to mitigate the outage risk
• Return Huntington Beach units 3 & 4 to service
• Accelerate Barre-Ellis transmission upgrade
• Complete Sunrise transmission line and related outage planning
• Fully fund Flex Alerts
• Fully utilize available demand response
• Seek additional military and public agency demand response
• Ensure that existing generation is well-maintained and available
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10. Where we stand once mitigation measures are
implemented
San Diego Los Angeles Basin
Without SONGS and
with Huntington Beach Without SONGS
3&4– and with HB 3 & 4
Import capability – Total gen
Total gen +3048 Total gen +9870
Import capability +2450 Import capability +10,771
Largest generation -603
Largest generation -498
outage
outage
Load -4882
Load -19,931
Reserve Margin = 13 Surplus = 212
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11. Demand response will help
• The benefits could be very helpful. The CPUC, CEC and ISO have worked
with the utilities to identify the functionality and quantify the specific location
of demand response programs.
On the critical transmission path: 78 MW
Elsewhere in LA where overloads possible: 428 MW
San Diego: 104 MW
• These utility demand response programs cannot replace Huntington Beach
3 and 4 but can reduce the required run time and increase operating
margins under hot summer loads.
• The specific reliability problem in southern California requires the response
to be automated. Current DR programs require manual deployment leaving
no time for operator action.
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12. SM
2012 Mitigation Measures
• Transmission – Del Amo-Ellis Loop-In Project
– Creates additional transmission capacity to serve South Orange
County
– Prevents line overloads and
improves voltage stability
– Modifies existing transmission
lines and structure upgrades
– Accelerated to be completed
by June 1, 2012
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13. SM
2012 Mitigation Measures continued
Generation – AES Huntington Beach
Units 3 and 4 (450 MW)
•Ordered by CAISO
•Returning Units 3 and 4 to service
•Provides needed generation and
voltage support
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14. SM
Demand Response Capability
• Existing Demand Response capability at substations
surrounding SONGS:
– Summer Discount Plan (AC Cycling) – 48 MW of existing SDP
resources
– Potential to add 5 to 8 MW
– Base Interruptible Program – 30 MW of existing BIP resources
• 10 for 10 Program (5 to 10 MW reduction potential)
– Commercial customer receives bill credit for usage reduction
– 10% bill credit for 10% reduction
– Compares usage from summer 2012 to summer 2011
– Program period: July 1- Sept. 30, 2012
– Available in Orange County only
– Only bundled customers not already on DR
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15. SM
Demand Response Capability continued
• Save Power Day (Peak Time Rebate) program (10
MW+ reduction potential in south Orange County)
– Available to all residential customers with smart meters
– Messaging to customers via notification signup and other
customer outreach
• Direct Install Program
– For small business customers
– Free installation of lighting and HVAC controls
– SCE and City of Irvine partnership
– Available June 2012
• Conservation outreach (statewide Flex Alert, local)
– Energy conservation messages in all customer communications
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16. SM
Collaboration and Communication with Irvine
and Community
• SCE is actively reaching out to:
– Public Safety and essential use facilities
– Irvine Unified School District
– University of California, Irvine
– Irvine Valley College
– Irvine Chamber of Commerce
– Irvine Ranch Water District
– Home Owners’ Associations (HOAs)
– Community based organizations
– Medical baseline/critical care customers
– Other
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17. SM
Questions?
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