Briefing on 2009 Summer Loads & Resources Operations - - PowerPoint PPT Presentation

Briefing on 2009 Summer Loads & Resources Operations Preparedness Assessment

Bob Emmert

• Sr. Loads & Resources Engineer

Board of Governors Meeting General Session May 18, 2009

Slide 2

! Ongoing California drought, now in 3rd year

! Reducing California hydro capacity & energy ! Impact on supply adequacy – Negative

! Reduced peak demand

! Recession impacting load ! Impact on supply adequacy - Helpful

In summer 2009, two key issues offset each other.

Supply

Demand

Slide 3

2009 water conditions improved since February, similar to 2008.

Summary of Water Conditions

May 1, 2009 (percent of average)

California - Statewide Precip Snow Water Content Reservoir Storage Runoff 2009 80% 60% 80% 60%

Previous Years May 1, 2008 85% 65% 85% 60% May 1, 2007 65% 25% 105% 55%

Slide 4

! Hydro scenario based on:

! Derates for units dependent on large reservoir storage ! RA capacity (1-in-5) for hydro units fed directly from show melt

! 2009 Hydro capacity derate scenario

NP26 hydro capacity derate 792 MW (79%) SP26 hydro capacity derate 208 MW (21%) ISO hydro capacity derate 1,000 MW

A hydro capacity/energy derate scenario was developed for 2009.

Slide 5

Peak Demands were lower in 2008.

Comparison of 2008 Demand to 2007

(Hot Days in August with Similar Weather)

99.0 98.2 48,491 44,511

20 40 60 80 100

8/31/2007 8/29/2008

631 Heat Index

10,000 20,000 30,000 40,000 50,000

Demand (MW)

631MaxHeat Index Peak Demand

Slide 6

For 2009 we used a range of economic scenarios to predict peak demand.

2009 baseline GDP forecast

Slide 7

All GDP baseline forecast predicts 2009 demand 3% lower than 2008.

CAISO Historical Loads and 1-in-2 Load Forecast Scenarios

Excluding Pumped Storage and Water Delivery Pumping Loads

38,000 39,000 40,000 41,000 42,000 43,000 44,000 45,000 46,000 47,000 48,000 49,000 50,000 51,000 52,000 2004 2005 2006 2007 2008 2009 1-in-2 2010 1-in-2 2011 1-in-2

Annual Peak Demand (MW)

Economic Base Case Economic Scenario-1 Economic Scenario-2 Economic Scenario-3 Economic Scenario-4

History Forecast

3%

Slide 8

2009 Summer planning reserve margins are more than adequate.

Resource Adequacy Planning Conventions CAISO SP26 NP26 Existing Generation 47,500 22,558 24,929 Retirements (Known) 22 22 High Probability CA Additions 1,476 378 1,098 Hydro Derates

• 1,000
• 208
• 792

Net Interchange (Moderate) 10,100 9,200 2,050 Total Net Supply (MW) 58,098 31,929 27,306 Demand (1-in-2 Summer Temperature) 45,379 25,412 21,370 DR & Interruptible Programs 2,090 1,496 593 Planning Reserve 32.6% 31.5% 30.6%

Summer 2009 Outlook

Slide 9

CAISO deterministic results indicate no firm load shedding in these scenarios.

CAISO 2009 Operating Reserves

(Nine Deterministic Scenarios)

2,000 4,000 6,000 8,000 10,000 12,000 14,000

High Imports (11,400 MW) Moderate Imports (10,100 MW) Low Imports (8,800 MW) Operating Reserve Margin (MW)

0% 3% 6% 9% 12% 15% 18% 21% 24% 27%

Operating Reserve Margin (%)

1-in-2 Demand & 1-in-2 Outages 1-in-5 Demand & 1-in-5 Outages 1-in-10 Demand & 1-in-10 Outages Firm Load Shedding

Slide 10

2009 probabilistic results show lower probability

• f shedding firm load versus 2008.

Probabilities of 3% Operating Reserve Margin

During Peak Conditions

(firm load shedding begins)

0.1% 3.7% 0.2% 10% 0.6% 3.8%

0% 2% 4% 6% 8% 10%

2008 2009

3% Operating Reserve

Probability of Occurrence During Peak Conditions

CAISO SP26 NP26

System & zonal are non- coincident

Slide 11

! Extended hotter than normal summer predicted (June-August) ! Continued need for high import levels seen during 2008 ! Increased risk from fires near transmission lines

Focus of preparation for 2009:

Situation manageable