HomeMy WebLinkAbout1b. 2021 Winter StormShort Supply & Winter Storm Event
Outreach
March 2021
Topics for Discussion
•Why Were Some Customers and Locations Not
Impacted?
•Rotating Outages versus Controlled Outages
•Was the Process Equitable?
•Critical Load and Critical Care Customers
•Communication
•Next Steps
3/1/2021 2
ERCOT Market Structure
•Oncor is a regulated TDU in ERCOT.
•Delivers electricity to more than 10M
Texans.
•Operates more than 139,000 miles of
T&D lines.
•Employs more than 4,000 Texans in
our service area.
•Service areas spans Permian Basin
to Piney Woods, and Red River to
Round Rock.
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GENERATORS
TRANSMISSION
& DISTRIBUTION
RETAIL ELECTRIC
PROVIDERS (REP)
COMPETITIVE
REGULATED
COMPETITIVE
0
5000
10000
15000
20000
25000
1:451:552:254:565:297:4612:5514:4717:3118:440:002:004:077:5710:5211:5813:3417:3922:1523:591:207:4310:4012:1814:1217:0219:3521:0923:202/15/2021 2/16/2021 2/17/2021
ERCOT Total Oncor Total
Load in MWs Oncor activities prior to the storm include:
•Pre-positioned personnel, equipment, and resources.
•Increased internal personnel and third-party contractors.
•Requested 2,363 mutual assistance FTEs from out-of-state
utilities.
•Opened & staffed System Emergency Center.
ERCOT Emergency Load Shed Event
Oncor Emergency Response
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•At the peak of the event, ERCOT directed TDUs to shed 20,000 MW of load to
ensure grid stability, and Oncor implemented its response accordingly.
•Oncor was ultimately directed to shed more than 7,200 MW of load, which:
•Was approximately 5 times as large as the last load-shedding event in 2011;
•At its peak, impacted approximately 1.3M customers in Oncor’s service area.
•Rapid response by Oncor and other TDUs ensured grid stability and avoided a
potential blackout of the entire ERCOT system.
•The magnitude of load shed made it impossible to employ limited-duration rotating
outages and reduce enough load to balance the system, leaving some Oncor
customers without power for an extended time period.
Load Shedding –Customer Impacts
•Necessary when electric supply
(generation) cannot support the level
of demand (load).
•Executed under the direction of grid
operators like ERCOT.
•Employed by ERCOT & TDUs as an
emergency response measure.
•Utilized to restore stability to the grid.
•Pre-planned manual process shared
as equitably as possible in the
communities we serve.
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•The amount of load shed requested
by ERCOT made it impossible to
employ limited-duration rotating
outages.
•Controlled outages were employed to
provide stability to the grid and to
maintain service to critical facilities
like hospitals and 911 centers.
•Unfortunately, controlled outages left
many of our customers without power
for an extended period of time.
•Customers were also impacted by
winter storm outages to equipment.
Without the ability to shed load, the grid potentially becomes imbalanced and can lead to a blackout.
OVERVIEW EMERGENCY
Items for further Review / Examination
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•Industry’s general approach to managing and responding to load shed events of this
magnitude.
•Continued collaboration with gas industry regarding their electrical needs.
•Better understanding the priorities of our cities with regard to water systems and
facilities.
•Developing analytics programs and processes that better help identify “other”
outages occurring during load shed events.
•Better communication with customers as to new information received from ERCOT,
timelines for restoration, and changing grid and operational conditions.
•Helping customers identify opportunities for reducing load during emergency events
(e.g., downtown dimming).