California Public Utilities Commission California Energy Commission Los
California Public Utilities Commission California Energy Commission Los Angeles Department of Water and Power Aliso Canyon’s Impact on Electric Reliability Technical Analysis and Action Plan Legislative Hearing May 10, 2016
DOGGR is overseeing comprehensive safety review • Goal: Ensure no other leaks at Aliso Canyon – Safety program developed in cooperation with independent technical experts from national labs • Gas may be injected into Aliso Canyon only after all 114 wells have passed comprehensive tests or have been isolated. • New injections could increase gas pressure, so all wells must be fully safe and operational or be separated from the reservoir • Unknowns: when safety review will be completed; if or how many wells will be cleared to operate; the ultimate production capability of the wells • DOGGR has issued emergency regulations for all gas storage facilities & is developing new permanent regulations – Includes limits on maximum pressure for all facilities, including Aliso Page 2
Working since December to understand reliability impacts and to develop action plan • In compliance with Governor’s Proclamation, reliability studies performed by CPUC, CEC, CAISO and LADWP • Relied on support from So. Cal. Gas to analyze operations impacts and curtailment scenarios • Technical Assessment Report and Draft Mitigation Action Plan Released on April 5 th and workshop on April 8 • Analysis focused on summer 2016 – Separate issues for next winter, yet to be fully assessed – Winter workshop planned for July or August • Report assessing long-term viability of natural gas storage; due in 2017 Page 3
Aliso Canyon has been drawn down to 15 Bcf • Agencies directed So. Cal. Gas to extract gas as quickly as possible to assist in reducing/stopping leak • Reliability analysis showed some Aliso gas is needed • Discontinued withdrawals per CPUC Order of 1/21/16 • Remaining 15 Bcf intended to: – help meet peak demand in recent winter – provide withdrawals for upcoming summer – support gas operations for winter 2016 • Uncertainty of remaining gas: Withdrawal capability shrinks as diminished inventory reduces field pressure Page 4
Aliso supports ~9, 800 MW: 40% LADWP/ 60% in CAISO; Critical for Peak Day and Contingency Reserve situations 5 Page 5
Capacity of pipe and other storage indicates general risk Supply/Demand System Design (Bcf/day) Actual Experience (Bcf/day) Pipeline Capacity Supply 3. 8 3. 0 Other Storage Supply (without Aliso) 1. 7 1. 0 5. 5 4. 0 -5. 0 0. 5 (1. 0) TOTAL SUPPLY Peak Winter Gas Demand RESERVE MARGIN • Typical outages can reduce capacity 0. 5 -1. 0 Bcf/day • Electric generation typically requires 1. 0 -2. 0 Bcf/day Page 6
Aliso Canyon used most days of year • • Aliso is the largest gas storage facility inside LA Basin; helps serve 11 million citizens Working capacity is 86 Bcf; daily withdrawal ~1. 8 Bcf; inject ~0. 4 Bcf Gas delivered into LA Basin is limited by pipeline capacity and velocity Gas from Aliso Canyon: – – • Helps to manage fast changes in pipe system flows Helps balance difference between scheduled gas and actual gas flows Aliso Canyon withdrawals occurred 134 of 151 “winter” days and 70 of 214 “summer” days: Average Days per Year Gas Withdrawn from Aliso (2012 2015) Page 7
Technical Assessment Group consisted of CAISO, CPUC, CEC, LADWP with input from So. Cal. Gas • Applied industry standard hydraulic model – Inputs include minimum and maximum acceptable operating pressures – Simulates gas flows and operating pressures during gas day – Used to determine when to add capacity or if new load can be served – Frequently tested against actual operations – So. Cal. Gas frequently performs modeling for third-parties consistent with PU Code on proprietary models Page 8
Simulated four actual operations days DATE CONDITION Demand (Bcf per Day) 9/16/14 LADWP Peak Day 3. 5 7/30/15 Large Electric Generation Ramp 3. 2 9/9/15 CAISO – Large Difference between Day Ahead and Real Time actual + LADWP 2015 Peak 3. 5 12/15/15 Winter Day and High Electric Generation 4. 0 • Assumptions: – Aliso Canyon considered unavailable – No planned or unplanned gas system outages – Honor Rancho, La Goleta fully used; Playa Del Rey used for reserve – Must restore system to neutral balance overnight to prevent cascading problems on subsequent days Page 9
Analysis indicated risks to reliability 1. Scheduled flowing gas can fail to meet actual demand 2. Planned and unplanned gas system outages can limit pipeline and other storage availability 3. Rapid ramping of electric generation can exceed dynamic capability of gas system - Recovering from contingencies - Following changes in renewable generation - Important: gas moves ~30 mph or less Page 10
Confirmed: Serious risk to gas/electric reliability this summer • If Aliso is not used, the LA area can expect 16 summer days of gas curtailment in 2016 – Electric generators are first to be curtailed • Up to 14 summer days may require electric service interruption, potentially to millions of customers Scenario Gas Quantity Curtailed Days of Gas Curtailment Risk for Electric Generators (Summer) A. 150 MMcf mismatch between scheduled gas and actual demand 180 MMcf 2 Not Likely B. Mismatch plus outage at other storage field 480 MMcf 2 Likely C. Mismatch plus pipeline outage 600 MMcf 9 Yes D. Mismatch plus outages both on other storage and pipeline 1100 MMcf 3 Yes Gas Curtailment Interrupts Electricity Service (Summer) Page 11
Mitigation measures help, but do not eliminate risks Page 12
Mitigation measures help, but do not eliminate risks Page 13
Response to comments raised • April 8 th public workshop in Porter Ranch garnered stakeholder participation • Some statements require clarification Statement A. The total gas system supply capability is 5. 7 Bcf B. Neighboring states like Arizona and Nevada do not need to rely on natural gas storage facilities C. It is not a concern that gas consumption in other states upstream of California could restrict supplies D. E. F. So. Cal. Gas flowing gas supply is not limited to its 3. 875 Bcfd of firm pipeline capacity. So. Cal. Gas can bring more gas in at the border, using the full 6. 1 Bcfd of interstate capacity that comes to the CA border. Was Play Del Rey storage considered in the hydraulic simulations? The critical issue on a peak day is how quickly a storage field can send gas into the pipeline system, and not the volume of gas in the storage field. Clarification Operational risk exists when there is a mismatch between if the gas supply is not scheduled to use the system relative to actual gas demand, rather than the total daily pipeline and storage withdraw capacity. Operators upstream of CA rely heavily on the “line pack” of their long pipeline systems, which is a form of storage. El Paso Natural Gas does have one storage field attached to it in New Mexico, and the pipelines in these states also have tighter balancing provisions than CA. There additional differences as well and shippers in both states suffer without storage. Southern California is at the far end of every interstate pipeline, and has seen supplies consumed by customers upstream during extreme weather conditions. While the capacity that comes to the border is in fact higher, So. Cal. Gas does not have the capacity to receive more than 3. 875 Bcfd into its system assuming all of its lines are fully operational. Playa Del Rey supply was used as reserve to meet system stress conditions. Both of the two simulation days with curtailment results in fact used gas from Playa Del Rey in virtually every hour of the day. The withdrawal capacity of a storage field is directly related to the inventory in the field. As the inventory is depleted due to storage utilization, the withdrawal deliverability is reduced. Page 14
A situation requiring unprecedented coordination • Based on the current design, Aliso is critical for integrated gas and electric service this summer • A distinct risk to reliability exists when mismatch of scheduled flow gas and actual gas demand exist while other planned outages to gas infrastructure occur • Mitigation measures will help, but do not eliminate risk • Next up: Analyze next winter • Consumer support is critical – Need all consumers to help when called upon during Flex Alerts by conserving – Rest of state can also help by conserving energy Page 15
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