Bal-003-1.1

Standard BAL-003-1.1 — Frequency Response and Frequency Bias Setting

A. Introduction
1.

Title: Frequency Response and Frequency Bias Setting

2.

Number: BAL-003-1.1

3.

Purpose: To require sufficient Frequency Response from the Balancing Authority (BA)
to maintain Interconnection Frequency within predefined bounds by arresting frequency
deviations and supporting frequency until the frequency is restored to its scheduled
value. To provide consistent methods for measuring Frequency Response and
determining the Frequency Bias Setting.

4.

Applicability:
4.1. Balancing Authority
4.1.1. The Balancing Authority is the responsible entity unless the Balancing
Authority is a member of a Frequency Response Sharing Group, in which
case, the Frequency Response Sharing Group becomes the responsible
entity.
4.2. Frequency Response Sharing Group

5.

Effective Date:
5.1. In those jurisdictions where regulatory approval is required, Requirements R2, R3
and R4 of this standard shall become effective the first calendar day of the first
calendar quarter 12 months after applicable regulatory approval. In those
jurisdictions where no regulatory approval is required, Requirements R2, R3 and
R4 of this standard shall become effective the first calendar day of the first calendar
quarter 12 months after Board of Trustees adoption.
5.2. In those jurisdictions where regulatory approval is required, Requirements R1 of
this standard shall become effective the first calendar day of the first calendar
quarter 24 months after applicable regulatory approval. In those jurisdictions
where no regulatory approval is required, Requirements R1 of this standard shall
become effective the first calendar day of the first calendar quarter 24 months after
Board of Trustees adoption.

B. Requirements
R1. Each Frequency Response Sharing Group (FRSG) or Balancing Authority that is not a
member of a FRSG shall achieve an annual Frequency Response Measure (FRM) (as
calculated and reported in accordance with Attachment A) that is equal to or more
negative than its Frequency Response Obligation (FRO) to ensure that sufficient
Frequency Response is provided by each FRSG or BA that is not a member of a FRSG
to maintain Interconnection Frequency Response equal to or more negative than the
Interconnection Frequency Response Obligation. [Risk Factor: High][Time Horizon:
Real-time Operations]

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Standard BAL-003-1.1 — Frequency Response and Frequency Bias Setting

R2. Each Balancing Authority that is a member of a multiple Balancing Authority
Interconnection and is not receiving Overlap Regulation Service and uses a fixed
Frequency Bias Setting shall implement the Frequency Bias Setting determined in
accordance with Attachment A, as validated by the ERO, into its Area Control Error
(ACE) calculation during the implementation period specified by the ERO and shall
use this Frequency Bias Setting until directed to change by the ERO. [Risk Factor:
Medium ][Time Horizon: Operations Planning]
R3. Each Balancing Authority that is a member of a multiple Balancing Authority
Interconnection and is not receiving Overlap Regulation Service and is utilizing a
variable Frequency Bias Setting shall maintain a Frequency Bias Setting that is: [Risk
Factor: Medium ][Time Horizon: Operations Planning]
3.1

Less than zero at all times, and

3.2

Equal to or more negative than its Frequency Response Obligation when
Frequency varies from 60 Hz by more than +/- 0.036 Hz.

R4. Each Balancing Authority that is performing Overlap Regulation Service shall modify
its Frequency Bias Setting in its ACE calculation, in order to represent the Frequency
Bias Setting for the combined Balancing Authority Area, to be equivalent to either:
[Risk Factor: Medium ][Time Horizon: Operations Planning]
•

The sum of the Frequency Bias Settings as shown on FRS Form 1 and FRS Form 2
for the participating Balancing Authorities as validated by the ERO, or

•

The Frequency Bias Setting shown on FRS Form 1 and FRS Form 2 for the entirety
of the participating Balancing Authorities’ Areas.

C. Measures
M1. Each Frequency Response Sharing Group or Balancing Authority that is not a member
of a Frequency Response Sharing Group shall have evidence such as dated data plus
documented formula in either hardcopy or electronic format that it achieved an annual
FRM (in accordance with the methods specified by the ERO in Attachment A with data
from FRS Form 1 reported to the ERO as specified in Attachment A) that is equal to or
more negative than its FRO to demonstrate compliance with Requirement R1.
M2. The Balancing Authority that is a member of a multiple Balancing Authority
Interconnection and is not receiving Overlap Regulation Service shall have evidence
such as a dated document in hard copy or electronic format showing the ERO validated
Frequency Bias Setting was implemented into its ACE calculation within the
implementation period specified or other evidence to demonstrate compliance with
Requirement R2.
M3. The Balancing Authority that is a member of a multiple Balancing Authority
Interconnection, is not receiving Overlap Regulation Service and is utilizing variable
Frequency Bias shall have evidence such as a dated report in hard copy or electronic
format showing the average clock-minute average Frequency Bias Setting was less
than zero and during periods when the clock-minute average frequency was outside of

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Standard BAL-003-1.1 — Frequency Response and Frequency Bias Setting

the range 59.964 Hz to 60.036 Hz was equal to or more negative than its Frequency
Response Obligation to demonstrate compliance with Requirement R3.
M4. The Balancing Authority shall have evidence such as a dated operating log, database or
list in hard copy or electronic format showing that when it performed Overlap
Regulation Service, it modified its Frequency Bias Setting in its ACE calculation as
specified in Requirement R4 to demonstrate compliance with Requirement R4.
D. Compliance
1.

Compliance Monitoring Process
1.1. Compliance Enforcement Authority
The Regional Entity is the Compliance Enforcement Authority except where the
responsible entity works for the Regional Entity. Where the responsible entity
works for the Regional Entity, the Regional Entity will establish an agreement
with the ERO or another entity approved by the ERO and FERC (i.e. another
Regional Entity), to be responsible for compliance enforcement.
1.2 Compliance Monitoring and Assessment Processes:
Compliance Audits
Self-Certifications
Spot Checking
Compliance Investigation
Self-Reporting
Complaints
1.3 Data Retention
The following evidence retention periods identify the period of time an entity is
required to retain specific evidence to demonstrate compliance. For instances
where the evidence retention period specified below is shorter than the time since
the last audit, the Compliance Enforcement Authority may ask an entity to
provide other evidence to show that it was compliant for the full time period since
the last audit.
The Balancing Authority shall retain data or evidence to show compliance with
Requirements R1, R2, R3 and R4, Measures M1, M2, M3 and M4 for the current
year plus the previous three calendar years unless directed by its Compliance
Enforcement Authority to retain specific evidence for a longer period of time as
part of an investigation.
The Frequency Response Sharing Group shall retain data or evidence to show
compliance with Requirement R1 and Measure M1 for the current year plus the
previous three calendar years unless directed by its Compliance Enforcement
Authority to retain specific evidence for a longer period of time as part of an
investigation.
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Standard BAL-003-1.1 — Frequency Response and Frequency Bias Setting

If a Balancing Authority or Frequency Response Sharing Group is found noncompliant, it shall keep information related to the non-compliance until found
compliant or for the time period specified above, whichever is longer.
The Compliance Enforcement Authority shall keep the last audit records and all
subsequent requested and submitted records.
1.4 Additional Compliance Information
For Interconnections that are also Balancing Authorities, Tie Line Bias control
and flat frequency control are equivalent and either is acceptable.
2.0 Violation Severity Levels
R#

Lower VSL

Medium VSL

High VSL

Severe VSL

R1

The Balancing
Authority’s, or
Frequency Response
Sharing Group’s,
FRM was less
negative than its
FRO by more than
1% but by at most
30% or 15 MW/0.1
Hz, whichever one
is the greater
deviation from its
FRO

The Balancing
Authority’s, or
Frequency Response
Sharing Group’s,
FRM was less
negative than its
FRO by more than
30% or by more
than 15 MW/0.1 Hz,
whichever is the
greater deviation
from its FRO

The Balancing
Authority’s, or
Frequency Response
Sharing Group’s,
FRM was less
negative than its
FRO by more than
1% but by at most
30% or 15 MW/0.1
Hz, whichever one is
the greater deviation
from its FRO

The Balancing
Authority’s, or
Frequency Response
Sharing Group’s,
FRM was less
negative than its
FRO by more than
30% or by more
than 15 MW/0.1 Hz,
whichever is the
greater deviation
from its FRO

R2

The Balancing
Authority in a
multiple Balancing
Authority
Interconnection and
not receiving
Overlap Regulation
Service and uses a
fixed Frequency
Bias Setting failed to
implement the
validated Frequency
Bias Setting value
into its ACE
calculation within
the implementation
period specified but
did so within 5

The Balancing
Authority in a
multiple Balancing
Authority
Interconnection and
not receiving
Overlap Regulation
Service and uses a
fixed Frequency
Bias Setting
implemented the
validated Frequency
Bias Setting value
into its ACE
calculation in more
than 5 calendar days
but less than or
equal to 15 calendar

The Balancing
Authority in a
multiple Balancing
Authority
Interconnection and
not receiving
Overlap Regulation
Service and uses a
fixed Frequency
Bias Setting
implemented the
validated Frequency
Bias Setting value
into its ACE
calculation in more
than 15 calendar
days but less than or
equal to 25 calendar

The Balancing
Authority in a
multiple Balancing
Authority
Interconnection and
not receiving
Overlap Regulation
Service and uses a
fixed Frequency
Bias Setting did not
implement the
validated Frequency
Bias Setting value
into its ACE
calculation in more
than 25 calendar
days from the
implementation

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Standard BAL-003-1.1 — Frequency Response and Frequency Bias Setting

R3

R4

calendar days from
the implementation
period specified by
the ERO.

days from the
implementation
period specified by
the ERO.

days from the
implementation
period specified by
the ERO.

period specified by
the ERO.

The Balancing
Authority that is a
member of a
multiple Balancing
Authority
Interconnection and
is not receiving
Overlap Regulation
Service and uses a
variable Frequency
Bias Setting average
Frequency Bias
Setting during
periods when the
clock-minute
average frequency
was outside of the
range 59.964 Hz to
60.036 Hz was less
negative than its
Frequency Response
Obligation by more
than 1% but by at
most 10%.
The Balancing
Authority
incorrectly changed
the Frequency Bias
Setting value used in
its ACE calculation
when providing
Overlap Regulation
Services with
combined footprint
setting-error less
than or equal to 10%
of the validated or
calculated value.

The Balancing
Authority that is a
member of a
multiple Balancing
Authority
Interconnection and
not receiving
Overlap Regulation
Service and uses a
variable Frequency
Bias Setting average
Frequency Bias
Setting during
periods when the
clock-minute
average frequency
was outside of the
range 59.964 Hz to
60.036 Hz was less
negative than its
Frequency Response
Obligation by more
than 10% but by at
most 20%.
The Balancing
Authority
incorrectly changed
the Frequency Bias
Setting value used in
its ACE calculation
when providing
Overlap Regulation
Services with
combined footprint
setting-error more
than 10% but less
than or equal to 20%
of the validated or
calculated value.

The Balancing
Authority that is a
member of a
multiple Balancing
Authority
Interconnection and
not receiving
Overlap Regulation
Service and uses a
variable Frequency
Bias Setting average
Frequency Bias
Setting during
periods when the
clock-minute
average frequency
was outside of the
range 59.964 Hz to
60.036 Hz was less
negative than its
Frequency Response
Obligation by more
than 20% but by at
most 30%.
The Balancing
Authority
incorrectly changed
the Frequency Bias
Setting value used in
its ACE calculation
when providing
Overlap Regulation
Services with
combined footprint
setting-error more
than 20% but less
than or equal to 30%
of the validated or
calculated value.

The Balancing
Authority that is a
multiple Balancing
Authority
Interconnection and
not receiving
Overlap Regulation
Service and uses a
variable Frequency
Bias Setting average
Frequency Bias
Setting during
periods when the
clock-minute
average frequency
was outside of the
range 59.964 Hz to
60.036 Hz was less
negative than its
Frequency Response
obligation by more
than 30%..

The Balancing
Authority
incorrectly changed
the Frequency Bias
Setting value used in
its ACE calculation
when providing
Overlap Regulation
Services with
combined footprint
setting-error more
than 30% of the
validated or
calculated value.
OR
The Balancing
Authority failed to
change the

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Standard BAL-003-1.1 — Frequency Response and Frequency Bias Setting

Frequency Bias
Setting value used in
its ACE calculation
when providing
Overlap Regulation
Services.
E. Regional Variance
None
F. Associated Documents
Procedure for ERO Support of Frequency Response and Frequency Bias Setting Standard
FRS Form 1
FRS Form 2
Frequency Response Standard Background Document
G. Version History
Version

Date

Action

Change Tracking

0

April 1, 2005

Effective Date

New

0

August 8, 2005

Errata

0

March 16, 2007

Removed "Proposed" from
Effective Date
FERC Approval — Order 693

0a

December 19,
2007

Added Appendix 1 
Interpretation of R3 approved
by BOT on October 23, 2007

Addition

0a

July 21, 2008

FERC Approval of
Interpretation of R3

Addition

0b

February 12,
2008

Added Appendix 2 
Interpretation of R2, R2.2, R5,
and R5.1 approved by BOT on
February 12, 2008

Addition

January 16, 2008

Section F: added “1.”; changed
hyphen to “en dash.” Changed
font style for “Appendix 1” to
Arial; updated version number
to “0.1b”

Errata

0.1b

New

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Standard BAL-003-1.1 — Frequency Response and Frequency Bias Setting

0.1b

October 29,
2008

BOT approved errata changes

Errata

0.1a

May 13, 2009

FERC Approved errata
changes – version changed to
0.1a (Interpretation of R2,
R2.2, R5, and R5.1 not yet
approved)

Errata

0.1b

May 21, 2009

FERC Approved Interpretation
of R2, R2.2, R5, and R5.1

Addition

1

February 7, 2013

Adopted by NERC Board of
Trustees

Complete Revision under
Project 2007-12

1

January 16, 2014

FERC Order issued approving
BAL-003-1. (Order becomes
effective for R2, R3, and R4
April 1, 2015. R1 becomes
effective April 1, 2016.)

1

May 7, 2014

NERC Board of Trustees
adopted revisions to VRF and
VSLs in Requirement R1.

1

November 26,
2014

FERC issued a letter order
approved VRF and VSL
revisions to Requirement R1.

1.1

August 25, 2015

Added numbering to
Introduction section, corrected
parts numbering for R3, and
adjusted font within section
M4.

Errata

1.1

November 13,
2015

FERC Letter Order approved
errata to BAL-003-1.1. Docket
RD15-6-000

Errata

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Standard BAL-003-1.1 — Frequency Response and Frequency Bias Setting

Attachment A
BAL-003-1 Frequency Response & Frequency Bias Setting Standard
Supporting Document
Interconnection Frequency Response Obligation (IFRO)
The ERO, in consultation with regional representatives, has established a target contingency protection
criterion for each Interconnection called the Interconnection Frequency Response Obligation (IFRO).
The default IFRO listed in Table 1 is based on the resource contingency criteria (RCC), which is the largest
category C (N-2) event identified except for the Eastern Interconnection, which uses the largest event in
the last 10 years. A maximum delta frequency (MDF) is calculated by adjusting a starting frequency for
each Interconnection by the following:
•
•

•
•

Prevailing UFLS first step
CCAdj which is the adjustment for the differences between 1-second and sub-second Point C
observations for frequency events. A positive value indicates that the sub-second C data is
lower than the 1-second data
CBR which is the statistically determined ratio of the Point C to Value B
BC’Adj which is the statistically determined adjustment for the event nadir being below the Value
B (Eastern Interconnection only) during primary frequency response withdrawal.

The IFRO for each Interconnection in Table 1 is then calculated by dividing the RCC MWs by 10 times the
MDF. In the Eastern Interconnection there is an additional adjustment (BC’Adj) for the event nadir being
below the Value B due to primary frequency response withdrawal. This IFRO includes uncertainty
adjustments at a 95 % confidence level. Detailed descriptions of the calculations used in Table 1 below
are defined in the Procedure for ERO Support of Frequency Response and Frequency Bias Setting
Standard.
Interconnection
Starting Frequency (FStart)
Prevailing UFLS First Step
Base Delta Frequency (DFBase)
CCADJ
Delta Frequency (DFCC)
CBR
Delta Frequency (DFCBR)
BC’ADJ
Max. Delta Frequency (MDF)
Resource Contingency Criteria
(RCC)
Credit for Load Resources
(CLR)
IFRO

Eastern
59.974
59.5*
0.474
0.007
0.467
1.000
0.467
0.018
0.449

Western
59.976
59.5
0.476
0.004
0.472
1.625
0.291
N/A
0.291

ERCOT
59.963
59.3
0.663
0.012
0.651
1.377
0.473
N/A
0.473

HQ
59.972
58.5
1.472
N/A
1.472
1.550
0.949
N/A
0.949

Units
Hz
Hz
Hz
Hz
Hz

4,500

2,740

2,750

1,700

MW

-1,002

300
-840

1,400**
-286

-179

MW
MW/0.1 Hz

Hz
Hz

Table 1: Interconnection Frequency Response Obligations

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Standard BAL-003-1.1 — Frequency Response and Frequency Bias Setting
*The Eastern Interconnection UFLS set point listed is a compromise value set midway between
the stable frequency minimum established in PRC-006-1 (59.3 Hz) and the local protection UFLS
setting of 59.7 Hz used in Florida and Manitoba.
**In the Base Obligation measure for ERCOT, 1400 MW (Load Resources triggered by Under
Frequency Relays at 59.70 Hz) was reduced from its Resource Contingency Criteria level of 2750
MW to get 239 MW/0.1 Hz. This was reduced to accurately account for designed response from
Load Resources within 30 cycles.
An Interconnection may propose alternate IFRO protection criteria to the ERO by submitting a SAR with
supporting technical documentation.
Balancing Authority Frequency Response Obligation (FRO) and Frequency Bias
Setting
The ERO will manage the administrative procedure for annually assigning an FRO and implementation of
the Frequency Bias Setting for each Balancing Authority. The annual timeline for all activities described
in this section are shown below.
For a multiple Balancing Authority interconnection, the Interconnection Frequency Response Obligation
shown in Table 1 is allocated based on the Balancing Authority annual load and annual generation. The
FRO allocation will be based on the following method:
FROBA = IFRO ×

Annual GenBA + Annual LoadBA
Annual GenInt + Annual LoadInt

Where:
• Annual GenBA is the total annual “Output of Generating Plants” within the Balancing Authority
Area (BAA), on FERC Form 714, column c of Part II - Schedule 3.
• Annual LoadBA is total annual Load within the BAA, on FERC Form 714, column e of Part II Schedule 3.
• Annual GenInt is the sum of all Annual GenBA values reported in that interconnection.
• Annual LoadInt is the sum of all Annual LoadBA values reported in that interconnection.
The data used for this calculation is from the most recently filed Form 714. As an example, a report to
NERC in January 2013 would use the Form 714 data filed in 2012, which utilized data from 2011.
Balancing Authorities that are not FERC jurisdictional should use the Form 714 Instructions to assemble
and submit equivalent data to the ERO for use in the FRO Allocation process.
Balancing Authorities that elect to form a FRSG will calculate a FRSG FRO by adding together the
individual BA FRO’s.
Balancing Authorities that elect to form a FRSG as a means to jointly meet the FRO will calculate their
FRM performance one of two ways:
•
•

Calculate a group NIA and measure the group response to all events in the reporting year on a
single FRS Form 1, or
Jointly submit the individual BAs’ Form 1s, with a summary spreadsheet that contains the sum
of each participant’s individual event performance.

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Standard BAL-003-1.1 — Frequency Response and Frequency Bias Setting
Balancing Authorities that merge or that transfer load or generation are encouraged to notify the ERO of
the change in footprint and corresponding changes in allocation such that the net obligation to the
Interconnection remains the same and so that CPS limits can be adjusted.
Each Balancing Authority reports its previous year’s Frequency Response Measure (FRM), Frequency
Bias Setting and Frequency Bias type (fixed or variable) to the ERO each year to allow the ERO to validate
the revised Frequency Bias Settings on FRS Form 1. If the ERO posts the official list of events after the
date specified in the timeline below, Balancing Authorities will be given 30 days from the date the ERO
posts the official list of events to submit their FRS Form 1.
Once the ERO reviews the data submitted in FRS Form 1 and FRS Form 2 for all Balancing Authorities,
the ERO will use FRS Form 1 data to post the following information for each Balancing Authority for the
upcoming year:
•
•

Frequency Bias Setting
Frequency Response Obligation (FRO)

Once the data listed above is fully posted, the ERO will announce the three-day implementation period
for changing the Frequency Bias Setting if it differs from that shown in the timeline below.
A BA using a fixed Frequency Bias Setting sets its Frequency Bias Setting to the greater of (in absolute
value):
•
•

Any number the BA chooses between 100% and 125% of its Frequency Response Measure as
calculated on FRS Form 1
Interconnection Minimum as determined by the ERO

For purposes of calculating the minimum Frequency Bias Setting, a Balancing Authority participating in a
Frequency Response Sharing Group will need to calculate its stand-alone Frequency Response Measure
using FRS Form 1 and FRS Form 2 to determine its minimum Frequency Bias Setting.
A Balancing Authority providing Overlap Regulation will report the historic peak demand and generation
of its combined BAs’ areas on FRS Form 1 as described in Requirement R4.
There are occasions when changes are needed to Bias Settings outside of the normal
schedule. Examples are footprint changes between Balancing Authorities and major changes in load or
generation or the formation of new Balancing Authorities. In such cases the changing Balancing
Authorities will work with their Regions, NERC and the Resources Subcommittee to confirm appropriate
changes to Bias Settings, FRO, CPS limits and Inadvertent Interchange balances.
If there is no net change to the Interconnection total Bias, the Balancing Authorities involved will agree
on a date to implement their respective change in Bias Settings. The Balancing Authorities and ERO will
also agree to the allocation of FRO such that the sum remains the same.
If there is a net change to the Interconnection total Bias, this will cause a change in CPS2 limits and FRO
for other Balancing Authorities in the Interconnection. In this case, the ERO will notify the impacted
Balancing Authorities of their respective changes and provide an implementation window for making
the Bias Setting changes.
Frequency Response Measure (FRM)
The Balancing Authority will calculate its FRM from Single Event Frequency Response Data (SEFRD),
defined as: “the data from an individual event from a Balancing Authority that is used to calculate its

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Standard BAL-003-1.1 — Frequency Response and Frequency Bias Setting
Frequency Response, expressed in MW/0.1Hz” as calculated on FRS Form 2 for each event shown on FRS
Form 1. The events in FRS Form 1 are selected by the ERO using the Procedure for ERO Support of
Frequency Response and Frequency Bias Setting Standard. The SEFRD for a typical Balancing Authority in
an Interconnection with more than one Balancing Authority is basically the change in its Net Actual
Interchange on its tie lines with its adjacent Balancing Authorities divided by the change in
Interconnection frequency. (Some Balancing Authorities may choose to apply corrections to their Net
Actual Interchange (NAI) values to account for factors such as nonconforming loads. FRS Form 1 and 2
shows the types of adjustments that are allowed. Note that with the exception of the Contingent BA
column, any adjustments made must be made for all events in an evaluation year. As an example, if an
entity has non-conforming loads and makes an adjustment for one event, all events must show the nonconforming load, even if the non-conforming load does not impact the calculation. This ensures that the
reports are not utilizing the adjustments only when they are favorable to the BA.) The ERO will use a
standardized sampling interval of approximately 16 seconds before the event up to the time of the
event for the pre-event NAI, and frequency (A values) and approximately 20 to 52 seconds after the
event for the post-event NAI (B values) in the computation of SEFRD values, dependent on the data scan
rate of the Balancing Authority’s Energy Management System (EMS).
All events listed on FRS Form 1 need to be included in the annual submission of FRS Forms 1 and 2. The
only time a Balancing Authority should exclude an event is if its tie-line data or its Frequency data is
corrupt or its EMS was unavailable. FRS Form 2 has instructions on how to correct the BA’s data if the
given event is internal to the BA or if other authorized adjustments are used.
Assuming data entry is correct FRS Form 1 will automatically calculate the Balancing Authority’s FRM for
the past 12 months as the median of the SEFRD values. A Balancing Authority electing to report as an
FRSG or a provider of Overlap Regulation Service will provide an FRS Form 1 for the aggregate of its
participants.
To allow Balancing authorities to plan its operations, events with a “Point C” that cause the
Interconnection Frequency to be lower than that shown in Table 1 above (for example, an event in the
Eastern Interconnection that causes the Interconnection Frequency to go to 59.4 Hz) or higher than an
equal change in frequency going above 60 Hz may be included in the list of events for that
interconnection. However, the calculation of the BA response to such an event will be adjusted to show
a frequency change only to the Target Minimum Frequency shown in Table 1 above (in the previous
example this adjustment would cause Frequency to be shown as 59.5 Hz rather than 59.4 HZ) or a high
frequency amount of an equal quantity. Should such an event happen, the ERO will provide additional
guidance.
Timeline for Balancing Authority Frequency Response and Frequency Bias Setting
Activities
Described below is the timeline for the exchange of information between the ERO and Balancing
Authorities (BA) to:
•
•
•

Facilitate the assignment of BA Frequency Response Obligations (FRO)
Calculate BA Frequency Response Measures (FRM)
Determine BA Frequency Bias Settings (FBS)

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Standard BAL-003-1.1 — Frequency Response and Frequency Bias Setting
Target Date

Activity

April 30

The ERO reviews candidate frequency events and selects frequency events for
the first quarter (December to February).

May 10

Form1 is posted with selected events from the first quarter for BA usage by the
ERO.

May 15

The BAs receive a request to provide load and generation data as described in
Attachment A to support FRO assignments and determining minimum FBS for
BAs.

July 15

The BAs provide load and generation data as described in Attachment A to the
ERO.

July 30

The ERO reviews candidate frequency events and selects frequency events for
the second quarter (March to May).

August 10

Form1 is posted with selected events from the first and second quarters for BA
usage by the ERO.

October 30

The ERO reviews candidate frequency events and selects frequency events for
the third quarter (June to August)

November 10

Form1 is posted with selected events from the first, second, and third quarters
for BA usage by the ERO.

November 20

If necessary, the ERO provides any updates to the necessary Frequency
Response.

November 20

The ERO provides the fractional responsibility of each BA for the
Interconnection’s FRO and Minimum FBS to the BAs.

January 30

The ERO reviews candidate frequency events and selects frequency events for
the fourth quarter (September to November).

2nd business day in
February

Form1 is posted with all selected events for the year for BA usage by the ERO.

February 10

The ERO assigns FRO values to the BAs for the upcoming year.

March 7

BAs complete their frequency response sampling for all four quarters and their
FBS calculation, returning the results to the ERO.

March 24

The ERO validates FBS values, computes the sum of all FBS values for each
Interconnection, and determines L10 values for the CPS 2 criterion for each BA
as applicable.

Any time during
first 3 business
days of April
(unless specified
otherwise by the
ERO)

The BA implements any changes to their FBS and L10 value.

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* FOR INFORMATIONAL PURPOSES ONLY *
Enforcement Dates: Standard BAL-003-1.1 — Frequency Response and Frequency Bias Setting
United States
Standard

Requirement

Enforcement Date

BAL-003-1.1

R1.

04/01/2016

BAL-003-1.1

R2.

11/13/2015

BAL-003-1.1

R3.

11/13/2015

BAL-003-1.1

3.1.

11/13/2015

BAL-003-1.1

3.2.

11/13/2015

BAL-003-1.1

R4.

11/13/2015

Inactive Date

Printed On: November 27, 2016, 07:31 PM