NERC Prep Test 2 Exam Questions and Answers-2025 Update.
A transaction of 100 MWs is scheduled out of your area at the top of the hour with a 10-
minute ramp. You have the following generation available: What combination of
generation would need to be used?
Generator Capacity Current MWs Ramp Capability
1 100 MW 50 MW 5 MW/min
2 100 MW 40 MW 3 MW/min
3 100 MW 50 MW 1 MW/min
4 100 MW 60 MW 2 MW/min - Correct Answer Generators 1, 2, 4
The Balancing Authority selling power to an end user entered the wrong schedule for
the upcoming hour. Which part of the ACE equation [ACE = (NIA - NIS) - 10B (FA - FS)
- IME], will cause Inadvertent Interchange to occur as the result of the incorrect
schedule? - Correct Answer Both the Interchange portion and frequency portion of the
Ace Equation will contribute
What is the most common cause of frequency fluctuations? - Correct Answer System
generation and load imbalance
A Balancing Authority's inadvertent accumulation reflects over-generation during on-
peak hours. When system load is decreasing, what actions could a Balancing Authority
system operator take to limit additional on peak inadvertent accumulation? - Correct
Answer Decrease transactions into their system
Decrease generation
Balancing Authority A is currently reading a system frequency of 59.98 Hz. Its Net
Actual Interchange is +100 MW and its Net Scheduled Interchange is +100 MW. If
Balancing Authority A's frequency bias setting is 100 MW/0.1 HZ, what is ACE? -
Correct Answer -20
Governor droop is expressed as: - Correct Answer A percentage of the frequency
change required for a governor to move a unit from no load to full load, or full load to no
load
, If the frequency bias setting is less negative than the frequency response of a Balancing
Authority and a frequency decline is caused by a sudden loss of generation in an
external balancing area, what will be the result? - Correct Answer The ACE will be
positive value and AGC will lower generation
Which of the following combinations would represent the best generation control
performance (in terms of helping the Interconnection's frequency) by a Balancing Area?
- Correct Answer ACE is positive while frequency is below 60
If a Balancing Authority has an ACE of -175 MW and Frequency is 59.85 Hz. Which
real-time Control Performance Standard maybe outside of its low limit? - Correct
Answer BAAL
For the ACE equation to work properly, dynamic schedules, pseudo ties, frequency, and
all ________________ must be metered. - Correct Answer Tie lines
Balancing Authority A is scheduled to import 300 MW but is only importing 260 MW.
Interconnection frequency is 59.94 and Balancing Authority A's Frequency Bias Setting
is -120 MW/0.1 Hz. What is Balancing Authority A's ACE reading? - Correct Answer -32
MW
A Balancing Authority has a Net Interchange Schedule of -250 MWs from 1200 to 1600
on a summer day. The Net Interchange Actual for those same hours respectively were -
230 MW, -275 MW, -250 MW and -270 MW. What was the Balancing Authority's
Inadvertent Interchange for the 4-hour period? - Correct Answer 25 MWs in
To conform to the CPS requirement, a Balancing Authority must have a _______. -
Correct Answer CPS1 greater than or equal to 100%
Of the following, which control system would be affected by a difference in Net Actual
Interchange and Net Scheduled Interchange? - Correct Answer Automatic Generation
Control
Preparations are being made to tie two islands together during restoration. Island "A"
has a frequency of 58.95 Hz and Island "B" has a frequency of 59.97 Hz. What action
should be taken to synchronize the two islands? - Correct Answer Shed load in Island
"A"
A transaction of 100 MWs is scheduled out of your area at the top of the hour with a 10-
minute ramp. You have the following generation available: What combination of
generation would need to be used?
Generator Capacity Current MWs Ramp Capability
1 100 MW 50 MW 5 MW/min
2 100 MW 40 MW 3 MW/min
3 100 MW 50 MW 1 MW/min
4 100 MW 60 MW 2 MW/min - Correct Answer Generators 1, 2, 4
The Balancing Authority selling power to an end user entered the wrong schedule for
the upcoming hour. Which part of the ACE equation [ACE = (NIA - NIS) - 10B (FA - FS)
- IME], will cause Inadvertent Interchange to occur as the result of the incorrect
schedule? - Correct Answer Both the Interchange portion and frequency portion of the
Ace Equation will contribute
What is the most common cause of frequency fluctuations? - Correct Answer System
generation and load imbalance
A Balancing Authority's inadvertent accumulation reflects over-generation during on-
peak hours. When system load is decreasing, what actions could a Balancing Authority
system operator take to limit additional on peak inadvertent accumulation? - Correct
Answer Decrease transactions into their system
Decrease generation
Balancing Authority A is currently reading a system frequency of 59.98 Hz. Its Net
Actual Interchange is +100 MW and its Net Scheduled Interchange is +100 MW. If
Balancing Authority A's frequency bias setting is 100 MW/0.1 HZ, what is ACE? -
Correct Answer -20
Governor droop is expressed as: - Correct Answer A percentage of the frequency
change required for a governor to move a unit from no load to full load, or full load to no
load
, If the frequency bias setting is less negative than the frequency response of a Balancing
Authority and a frequency decline is caused by a sudden loss of generation in an
external balancing area, what will be the result? - Correct Answer The ACE will be
positive value and AGC will lower generation
Which of the following combinations would represent the best generation control
performance (in terms of helping the Interconnection's frequency) by a Balancing Area?
- Correct Answer ACE is positive while frequency is below 60
If a Balancing Authority has an ACE of -175 MW and Frequency is 59.85 Hz. Which
real-time Control Performance Standard maybe outside of its low limit? - Correct
Answer BAAL
For the ACE equation to work properly, dynamic schedules, pseudo ties, frequency, and
all ________________ must be metered. - Correct Answer Tie lines
Balancing Authority A is scheduled to import 300 MW but is only importing 260 MW.
Interconnection frequency is 59.94 and Balancing Authority A's Frequency Bias Setting
is -120 MW/0.1 Hz. What is Balancing Authority A's ACE reading? - Correct Answer -32
MW
A Balancing Authority has a Net Interchange Schedule of -250 MWs from 1200 to 1600
on a summer day. The Net Interchange Actual for those same hours respectively were -
230 MW, -275 MW, -250 MW and -270 MW. What was the Balancing Authority's
Inadvertent Interchange for the 4-hour period? - Correct Answer 25 MWs in
To conform to the CPS requirement, a Balancing Authority must have a _______. -
Correct Answer CPS1 greater than or equal to 100%
Of the following, which control system would be affected by a difference in Net Actual
Interchange and Net Scheduled Interchange? - Correct Answer Automatic Generation
Control
Preparations are being made to tie two islands together during restoration. Island "A"
has a frequency of 58.95 Hz and Island "B" has a frequency of 59.97 Hz. What action
should be taken to synchronize the two islands? - Correct Answer Shed load in Island
"A"
