NERC PREP CERTIFICATION PAPER 2026
FULL SOLUTION GRADED A+
● A Balancing Authority has a sudden loss of a large block of load in its
area. This loss will be seen instantaneously in the change of which of the
following values?
1. Actual Net Interchange
2. Scheduled Frequency
3. Scheduled Net Interchange
4. Area Control Error
A) 4 only
B) 1 & 3
C) 1 & 4
D) 3 & 4 Answer: C) 1 & 4
● Metered Data included in the calculation of ACE are: dynamic
schedules, pseudo ties, actual frequency, and all __________.
A) Tie lines readings
,B) Generators output
C) Scheduled frequency indications
D) Transformer load Answer: A) Tie lines readings
● Balancing Authority A is currently reading a system frequency of
60.00 Hz. Its Net Actual Interchange is +100 MW and its Net Scheduled
Interchange is +200 MW. If Balancing Authority A's frequency bias
setting is 100 MW/0.1 Hz, what is ACE?
A) -100
B) 0
C) 10
D) 100 Answer: A) -100
● 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?
A) 6 MWs out
B) 25 MWs in
C) 25 MWs out
D) 6 MWs in Answer: B) 25 MWs in
,● For the ACE equation to work properly, dynamic schedules, pseudo
ties, frequency, and all ________________ must be metered.
A) Generation
B) Communications
C) Transformers
D) Tie lines Answer: D) Tie lines
● If the frequency bias setting is set to a less negative value than the
frequency response of a Balancing Authority and a frequency increase is
caused by a sudden loss of load in an external balancing area, what will
be the result?
A) The ACE will be zero and will take no AGC action
B) The ACE will be a negative value and AGC will increase generation
C) The ACE will be a positive value and AGC will lower generation
D)This will not affect the ACE Answer: B) The ACE will be a negative
value and AGC will increase generation
, ● 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?
A) The ACE will be a negative value and AGC will increase generation.
B) This will not affect the ACE.
C) The ACE will be a positive value and AGC will lower generation.
D) The ACE will be zero and will take no AGC action. Answer: C) The
ACE will be a positive value and AGC will lower generation.
● It is the responsibility of which entity/entities to develop, maintain,
and implement load shedding plans?
A) Transmission Operators and Balancing Authorities
B) Reliability Coordinator
C) Load Serving Entities
FULL SOLUTION GRADED A+
● A Balancing Authority has a sudden loss of a large block of load in its
area. This loss will be seen instantaneously in the change of which of the
following values?
1. Actual Net Interchange
2. Scheduled Frequency
3. Scheduled Net Interchange
4. Area Control Error
A) 4 only
B) 1 & 3
C) 1 & 4
D) 3 & 4 Answer: C) 1 & 4
● Metered Data included in the calculation of ACE are: dynamic
schedules, pseudo ties, actual frequency, and all __________.
A) Tie lines readings
,B) Generators output
C) Scheduled frequency indications
D) Transformer load Answer: A) Tie lines readings
● Balancing Authority A is currently reading a system frequency of
60.00 Hz. Its Net Actual Interchange is +100 MW and its Net Scheduled
Interchange is +200 MW. If Balancing Authority A's frequency bias
setting is 100 MW/0.1 Hz, what is ACE?
A) -100
B) 0
C) 10
D) 100 Answer: A) -100
● 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?
A) 6 MWs out
B) 25 MWs in
C) 25 MWs out
D) 6 MWs in Answer: B) 25 MWs in
,● For the ACE equation to work properly, dynamic schedules, pseudo
ties, frequency, and all ________________ must be metered.
A) Generation
B) Communications
C) Transformers
D) Tie lines Answer: D) Tie lines
● If the frequency bias setting is set to a less negative value than the
frequency response of a Balancing Authority and a frequency increase is
caused by a sudden loss of load in an external balancing area, what will
be the result?
A) The ACE will be zero and will take no AGC action
B) The ACE will be a negative value and AGC will increase generation
C) The ACE will be a positive value and AGC will lower generation
D)This will not affect the ACE Answer: B) The ACE will be a negative
value and AGC will increase generation
, ● 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?
A) The ACE will be a negative value and AGC will increase generation.
B) This will not affect the ACE.
C) The ACE will be a positive value and AGC will lower generation.
D) The ACE will be zero and will take no AGC action. Answer: C) The
ACE will be a positive value and AGC will lower generation.
● It is the responsibility of which entity/entities to develop, maintain,
and implement load shedding plans?
A) Transmission Operators and Balancing Authorities
B) Reliability Coordinator
C) Load Serving Entities
