ERCOT TEST PREP QUESTIONS WITH CORRECT ANSWERS LATEST UPDATE 2026/2027
When was the first ERCOT system connection and who was involved? - Answers 1924 between
Texas Power & Light and West Texas Systems
List the major NERC Interconnections & Loading - Answers ERCOT - 70-80K MW, Eastern - 600K
MW, Western - 125K MW, Quebec - 30K MW
How much of total Texas load does ERCOT cover? - Answers 85%
How does ERCOT connect to other entities? - Answers 5 AC-DC-AC Ties (DC Ties) - Monticello &
Oklaunion to SPP, Eagle Pass, Mcallen, & Laredo to CFE
How many entities make up the Eastern Interconnection - Answers 6:
FRCC - Florida Reliability Coordinating Council
MRO - Midwest Reliability Organization
NPCC - Northeast Power Coordinating Council
RFC - Reliability First Corporation
SERC - Southeast Reliability Corporation
SPP - Southwest Power Pool Reliability Utility
True or False: Municipally Owned Utilities must opt into retail competition - Answers False
How much of the ERCOT energy market is made up of Bi-Lateral transactions? - Answers 90-
95%
What makes up Ancillary Services? - Answers Regulation Reserve, Responsive Reserve (RRS),
Non-spinning Reserve (Non-spin)
Define Transmission Congestion - Answers System is approaching limits (thermal or load based)
& at risk
List the market participants - Answers QSE - Qualified Scheduling Entity
RE - Resource Entity
LSE - Load Serving Entity
CR - Competitive Retailer
TDSP - Transmission and Distribution Service Provider
NOIE - Non Opt-In Entity
,Other - Power Marketers (Buy and sell energy), Aggregators (Represent 1 or more retail
customers)
What subcommittees make up the technical advisory committee? - Answers PRS - Protocol
Revision Subcommittee
WSS - Wholesale Market Subcommittee
RSS - Retail Market Subcommittee
ROS - Reliability & Operations Subcommittee
COPS - Commercial Operations Subcommittee
What is the purpose of ERCOT? - Answers To maintain continuous surveillance of status of
operating conditions and act as the central information collection and dissemination point for
the market participants for system security purposes.
List ERCOT Responsibilities - Answers 1. Coordinate system-wide response to unusual
operating conditions like short supply, initiation of EEA & load shedding.
2. Manage ancillary services & anticipating shortages.
3. Monitor/coordinate transmission facility operations
4. Analysis of planned outage effect on bulk electric systems.
5. Monitor/control information for daily planning, hourly reporting, minute-by-minute operations.
6. Reporting for significant events to market participants
7. Reporting & adjusting accumulated time error.
List the ERCOT Core Processes - Answers Registration, Market operations, Power operations,
Load profiling, Data Acquisition & Aggregation, Settlements, Billing and Financial Transfer
What makes up the Day-Ahead Operations? - Answers The Day-Ahead Market (DAM) from 0600-
1430 and Day-Ahead Reliability Unit Committment (DRUC) from 1430-1800.
What is the purpose of the DRUC? - Answers Ensure reliability for the ERCOT grid.
What is the Adjustment Period? - Answers From 1800 to beginning of operating hour of
following day for each operating hour
What can QSEs and ERCOT do during the Adjustment Period? - Answers QSEs can:
- submit/update offers, trades, and schedules
- request resource de-commitments
, ERCOT can:
-implement the Supplemental Ancillary Services Market (SASM)
What are the difference levels of transmission voltages and how many miles of transmission
line does ERCOT own for each level? - Answers 69 KV - Greater than 11,000 miles
138 KV - 20,000 miles
345 KV - 9,500 miles
Total - Greater than 40,000 miles
Describe the transmission system reliability criteria - Answers Power system operated such that
a credible single contingency (i.e. outage of two generating units in a short period of time or
loss of 345 KV line) will not cause:
- Uncontrolled Breakup (Cascading Outage)
- Uncontrolled System Overloads
- Customer Outages
- Unacceptable Voltages
True or False: All outages 138 KV or below are not required to be reported to ERCOT. - Answers
False: All outages 60 KV or above must be submitted to ERCOT.
Who submits the outage schedule to ERCOT?
How long in advance to they submit? - Answers Transmission Service Provider (TSP)
12 months
What is the most important part of writing switching orders? - Answers SAFETY
What are two categories of outages? - Answers Transmission and Resource
What are the types of transmission outages? - Answers Planned, Maintenance, Forced,
Remedial, Opportunity, Simple
What are the types of resource outages? - Answers Planned, Forced, Maintenance, Opportunity
Describe the level of maintenance outages - Answers Level 1 - Equipment removed from service
within 24 hours to prevent forced outage. Requires ERCOT notification & justification.
Level 2 - Equipment removed from service within 2-7 days to prevent forced outage
Level 3 - Equipment removed from service within 8-30 days to prevent forced outage
When was the first ERCOT system connection and who was involved? - Answers 1924 between
Texas Power & Light and West Texas Systems
List the major NERC Interconnections & Loading - Answers ERCOT - 70-80K MW, Eastern - 600K
MW, Western - 125K MW, Quebec - 30K MW
How much of total Texas load does ERCOT cover? - Answers 85%
How does ERCOT connect to other entities? - Answers 5 AC-DC-AC Ties (DC Ties) - Monticello &
Oklaunion to SPP, Eagle Pass, Mcallen, & Laredo to CFE
How many entities make up the Eastern Interconnection - Answers 6:
FRCC - Florida Reliability Coordinating Council
MRO - Midwest Reliability Organization
NPCC - Northeast Power Coordinating Council
RFC - Reliability First Corporation
SERC - Southeast Reliability Corporation
SPP - Southwest Power Pool Reliability Utility
True or False: Municipally Owned Utilities must opt into retail competition - Answers False
How much of the ERCOT energy market is made up of Bi-Lateral transactions? - Answers 90-
95%
What makes up Ancillary Services? - Answers Regulation Reserve, Responsive Reserve (RRS),
Non-spinning Reserve (Non-spin)
Define Transmission Congestion - Answers System is approaching limits (thermal or load based)
& at risk
List the market participants - Answers QSE - Qualified Scheduling Entity
RE - Resource Entity
LSE - Load Serving Entity
CR - Competitive Retailer
TDSP - Transmission and Distribution Service Provider
NOIE - Non Opt-In Entity
,Other - Power Marketers (Buy and sell energy), Aggregators (Represent 1 or more retail
customers)
What subcommittees make up the technical advisory committee? - Answers PRS - Protocol
Revision Subcommittee
WSS - Wholesale Market Subcommittee
RSS - Retail Market Subcommittee
ROS - Reliability & Operations Subcommittee
COPS - Commercial Operations Subcommittee
What is the purpose of ERCOT? - Answers To maintain continuous surveillance of status of
operating conditions and act as the central information collection and dissemination point for
the market participants for system security purposes.
List ERCOT Responsibilities - Answers 1. Coordinate system-wide response to unusual
operating conditions like short supply, initiation of EEA & load shedding.
2. Manage ancillary services & anticipating shortages.
3. Monitor/coordinate transmission facility operations
4. Analysis of planned outage effect on bulk electric systems.
5. Monitor/control information for daily planning, hourly reporting, minute-by-minute operations.
6. Reporting for significant events to market participants
7. Reporting & adjusting accumulated time error.
List the ERCOT Core Processes - Answers Registration, Market operations, Power operations,
Load profiling, Data Acquisition & Aggregation, Settlements, Billing and Financial Transfer
What makes up the Day-Ahead Operations? - Answers The Day-Ahead Market (DAM) from 0600-
1430 and Day-Ahead Reliability Unit Committment (DRUC) from 1430-1800.
What is the purpose of the DRUC? - Answers Ensure reliability for the ERCOT grid.
What is the Adjustment Period? - Answers From 1800 to beginning of operating hour of
following day for each operating hour
What can QSEs and ERCOT do during the Adjustment Period? - Answers QSEs can:
- submit/update offers, trades, and schedules
- request resource de-commitments
, ERCOT can:
-implement the Supplemental Ancillary Services Market (SASM)
What are the difference levels of transmission voltages and how many miles of transmission
line does ERCOT own for each level? - Answers 69 KV - Greater than 11,000 miles
138 KV - 20,000 miles
345 KV - 9,500 miles
Total - Greater than 40,000 miles
Describe the transmission system reliability criteria - Answers Power system operated such that
a credible single contingency (i.e. outage of two generating units in a short period of time or
loss of 345 KV line) will not cause:
- Uncontrolled Breakup (Cascading Outage)
- Uncontrolled System Overloads
- Customer Outages
- Unacceptable Voltages
True or False: All outages 138 KV or below are not required to be reported to ERCOT. - Answers
False: All outages 60 KV or above must be submitted to ERCOT.
Who submits the outage schedule to ERCOT?
How long in advance to they submit? - Answers Transmission Service Provider (TSP)
12 months
What is the most important part of writing switching orders? - Answers SAFETY
What are two categories of outages? - Answers Transmission and Resource
What are the types of transmission outages? - Answers Planned, Maintenance, Forced,
Remedial, Opportunity, Simple
What are the types of resource outages? - Answers Planned, Forced, Maintenance, Opportunity
Describe the level of maintenance outages - Answers Level 1 - Equipment removed from service
within 24 hours to prevent forced outage. Requires ERCOT notification & justification.
Level 2 - Equipment removed from service within 2-7 days to prevent forced outage
Level 3 - Equipment removed from service within 8-30 days to prevent forced outage
