I-SEM Rules
Trading and Settlement Code
Calculation of Payments and Charges
Interim Legal Draft
02/06/2016
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A. CALCULATION OF PAYMENTS AND CHARGES
A.1
INTRODUCTION
A.1.1
Purpose of this Chapter
A.1.1.1
This chapter specifies how the Market Operator shall calculate the charges
and payments for settlement of the Balancing Market and Imbalances.
A.1.2
Settlement Charges and Payments for Generator Units
A.1.2.1
The Market Operator shall calculate the following charges and payments for
each Generator Unit for the relevant period, in accordance with the timetable
in section [ ]:
(a)
CIMBuγ, the Imbalance Component Payment or Charge calculated in
accordance with section A.5;
(b)
CPREMIUMuγ, the Premium Component Payment calculated in
accordance with section A.6;
(c)
CDISCOUNTuγ, the Discount Component Payment calculated in
accordance with section A.6;
(d)
CAOOPOuγ, the Offer Price Only Accepted Offer Payment or Charge
calculated in accordance with section A.7;
(e)
CABBPOuγ, the Bid Price Only Accepted Bid Payment or Charge
calculated in accordance with section A.7;
(f)
CCURLuγ, the Curtailment Charge calculated in accordance with
section A.8;
(g)
CUNIMBuγ, the Uninstructed Imbalance Charge calculated in
accordance with section A.9;
(h)
CIIuγ, the Information Imbalance Charge calculated in accordance
with section A.10;
(i)
CFCuk, the Fixed Cost Payment or Charge calculated in accordance
with section A.11; and
(j)
CTESTuγ, the Testing Charge calculated in accordance with section
A.13.
A.1.3
Settlement Charges and Payments for Supplier Units
A.1.3.1
The Market Operator shall calculate the following charges and payments for
each Supplier Unit for the relevant period, in accordance with the timetable in
section [ ]:
(a)
CIMBvγ, the Imbalance Component Payment or Charge calculated in
accordance with section A.5;
(b)
CIMPvγ, the Imperfections Charge calculated in accordance with
section A.12;
(c)
CREVvγ, the Residual Error Volume Charge calculated in accordance
with section A.14; and
(d)
CCAvγ, the Currency Adjustment Payment or Charge calculated in
accordance with section A.15.
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A.2
DATA SOURCES, CONVENTIONS AND DEFINITIONS
Explanatory notes

To define the source of each variable and parameter required for the purposes of
settlement calculations;

To define calculations the Market Operator needs to carry out on data which is used
in multiple components of calculations throughout this section.

To define conventions required for the understanding of this section. These may at a
future time be moved to a general interpretations section for the code, rather than a
specific section for this aspect of the rules.
A.2.1
Definitions
A.2.1.1
For each Imbalance Pricing Period, φ, and each Imbalance Settlement
Period, γ, as applicable for the relevant process, for the purposes of this
Code the Bid Offer Acceptance subscript, o, resets to zero so that the first
Bid Offer Acceptance in the period has a subscript value of o = 1.
A.2.1.2
The Market Operator shall set the value of a variable at zero where this Code
states that a provision does not apply to a unit, and where the variable which
is the result of that provision is to be used in a later process for that unit.
A.2.1.3
The Market Operator shall determine whether a Pumped Storage Generator
Unit, u, is in Pumping Mode for the purposes of [the calculations in] this Code
as follows:
(a)
If the value of a Pumped Storage Unit’s Dispatch Quantity (qDuoγ(t)) at
all times within an Imbalance Settlement Period, γ, is entirely positive
(i.e. in the generating range of the unit’s output), then the unit is
deemed to be in Generating Mode for the entirety of that Imbalance
Settlement Period;
(b)
If the value of a Pumped Storage Unit’s Dispatch Quantity (qDuoγ(t)) at
any time within an Imbalance Settlement Period, γ, is negative (i.e. in
the pumping range of the unit’s output), then the unit is deemed to be
in Pumping Mode for the entirety of that Imbalance Settlement Period.
A.2.1.4
An “incremental action” (“Inc”) is a System Operator action intended to
increase the power (MW) or energy (MWh) being sent out into the system, or
decrease the power or energy being taken from the system. Inc power or
energy quantities are positive, resulting from the Dispatch Quantity being
higher than the Physical Notification Quantity for a unit at any point in time.
Incremental actions are represented in settlement through Accepted Offer
Quantities.
A.2.1.5
A decremental action (“Dec”) is a System Operator action intended to
decrease the power (MW) or energy (MWh) being sent out into the system,
or increase the power or energy being taken from the system. Dec power or
energy quantities are negative, resulting from the Dispatch Quantity being
lower than the Physical Notification Quantity for a unit at any point in time.
Decremental actions are represented in settlement through Accepted Bid
Quantities.
A.2.1.6
Variables for power (expressed as MW) quantities begin with a lower case
“q”, while variables for energy (expressed as MWh) quantities begin with an
upper case “Q”.
A.2.1.7
A Scheduling Agent is the entity or entities with the task of providing
schedules from market participants to TSOs, or where applicable third
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parties, in accordance with [Guideline on Electricity Transmission System
Operation].
A.2.1.8
A variable which is a function of time may have a different value at each time
within an Imbalance Settlement Period, γ, or Trading Period, h, rather than a
single fixed value defined for all times within an Imbalance Settlement
Period, γ, or Trading Period, h. Such variables are represented with the
inclusion of the notation ‘(t)’ at the end of the variable term.
A.2.1.9
The Interconnector Data Submission Point is the notional point at which the
Interconnector Residual Capacity Units and Interconnector Error Units are
deemed to be joined to the SEM and at which relevant metered values are
collected, prior to Loss-Adjustment and in respect of the transmission of
electricity across an Interconnector into SEM.
A.2.2
Sign Conventions
A.2.2.1
All values that relate to power (MW) or energy (MWh) being input into the
SEM are positive values. All values that relate to power (MW) or energy
(MWh) being taken from the SEM are negative values.
A.2.2.2
All values that relate to amounts (in € or £) due to a Participant or in respect
of a unit from the Market Operator are to be treated for the purposes of the
calculations set out in this Code as having positive values. All values that
relate to amounts (in € or £) due from a Participant or in respect of a unit to
the Market Operator are to be treated for the purposes of the calculations set
out in this Code as having negative values.
A.2.2.3
All values for power (MW) or energy (MWh) that relate to imports into the
SEM in relation to an Interconnector, Interconnector Residual Capacity Units
or Interconnector Error Unit shall be treated for the purposes of the
calculations set out in this Code as having positive or zero values. All values
for power (MW) or energy (MWh) that relate to exports from the SEM in
relation to an Interconnector, an Interconnector Residual Capacity Units or
an Interconnector Error Unit shall be treated for the purposes of the
calculations set out in this Code as having negative or zero values.
A.2.2.4
All values for power (MW), ramp rates (MW/min) or energy (MWh) and which
are not Loss-Adjusted in relation to an Interconnector, Interconnector
Residual Capacity Units or Interconnector Error Units shall be those
applicable at the Interconnector Data Submission Point.
A.2.3
Ex-Ante Market Data
A.2.3.1
The Scheduling Agent for each Participant shall submit to the Market
Operator details of the Contracted Quantities from the ex-ante markets (the
Day-ahead Trade Quantities and Intraday Trade Quantities, QTDAxuh,
QTIDxuh, QTDAxvh and QTIDxvh), the durations relevant to the trades (Dayahead Trade Duration and Intraday Trade Duration, DTDAx and DTIDx), and
the prices relevant to those quantities (the Day-ahead Trade Price and
Intraday Trade Price, PTDAxuh, PTIDxuh, PTDAxvh and PTIDxvh), for each
Generator Unit, u, and each Supplier Unit, v, of the Participant, for each
Trade, x, in each Period, h, in this context meaning the Day-ahead and
Intraday Trading Periods.
A.2.3.2
The value of the Ex-Ante Quantity (QEXuγ and QEXvγ) for each Generator
Unit and each Supplier Unit, v, in each Imbalance Settlement Period, γ, shall
be deemed to be zero if the Market Operator has not received values of the
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Contracted Quantities from the ex-ante markets by the time it is required to
carry out the Settlement calculations.
A.2.3.3
The Scheduling Agent for each Interconnector shall submit to the Market
Operator the Intraday Interconnector Schedule Quantities (QICSIDlh) for that
Interconnector, l, relevant to the calculation of Charges and Payments, in
each Period, h, in this context meaning the Intraday Trading Period.
A.2.4
Physical Notification Data
A.2.4.1
For the purposes of calculating the Information Imbalance Charge in
accordance with section A.10, the PN Submission Period, β, means each
half-hour period between 13:30 TD-1 and the Gate Closure time for an
Imbalance Settlement Period during which a Participant may submit Physical
Notification Data in respect of that Imbalance Settlement Period.
A.2.4.2
For all purposes not covered under paragraph A.2.4.1, the subscript, β,
refers to the time Physical Notification Data or Commercial Offer Data, as the
case may be, was Accepted.
A.2.4.3
The value of the Final Physical Notification Quantity (qFPNuh(t)) for each
Generator Unit, u, which has Priority Dispatch, and which is nondispatchable, shall at all times in Period, h, be deemed to be equal to the
Outturn Availability Quantity (qAVAILOuh(t)) of the unit.
A.2.4.4
The Market Operator shall derive the Physical Notification Quantity (QPNuβγ)
for Generator Unit, u, in PN Submission Period, β, for Imbalance Settlement
Period, γ, by integrating the associated function of time Physical Notification
Quantity (qPNuβγ(t)) from the Accepted Physical Notification Data prevailing
at the end of that PN Submission Period, with respect to time across the
Imbalance Settlement Period.
A.2.4.5
The Market Operator shall derive the Final Physical Notification Quantity
(QFPNuγ) for Generator Unit, u, in Imbalance Settlement Period, γ, by
integrating the associated function of time Final Physical Notification Quantity
(qFPNuγ(t)), determined in accordance with [section in Data Submission],
with respect to time across the Imbalance Settlement Period.
A.2.4.6
The Market Operator shall derive the Final Physical Notification Quantity
(QFPNlγ) for Interconnector, l, in Imbalance Settlement Period, γ, by
integrating the associated function of time Final Physical Notification Quantity
(qFPNlγ(t)), determined in accordance with paragraph A.2.5.4, with respect to
time across the Imbalance Settlement Period.
A.2.5
Dispatch Data
A.2.5.1
Each System Operator shall submit to the Market Operator the Dispatch
Instructions in respect of each Generator Unit that is registered within its
Jurisdiction, and may submit an associated Ramp Rate and curtailment flag
for each Dispatch Instruction.
A.2.5.2
Each System Operator shall submit information referred to in paragraph
A.2.5.1 to the Market Operator in accordance with [Appendix K “Market Data
Transactions”], based on Outturn Data, and the values submitted shall be net
of Unit Load.
A.2.5.3
Except as provided in paragraph A.2.5.6(a), the Market Operator shall derive
the value of the Dispatch Quantity (qDuoh(t)) for each Generator Unit, u, for
each Bid Offer Acceptance, o, in Period, h, in accordance with [Appendix O
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“Instruction Profiling Calculations”], from the Dispatch Instructions submitted
by the relevant System Operator.
Explanatory Note
The following two paragraphs may need to be moved to a different section of the code –
this section relates to the settlement calculations, while the paragraphs below relate to
trading activities.
A.2.5.4
[A System Operator shall be entitled under the terms of the Code to make
SO Interconnector Trades.]
A.2.5.5
[A System Operator shall not conduct any SO Interconnector Trades before it
calculates the Final Physical Notification Quantity (qFPNlh(t)) of the
Interconnector for the relevant balancing market Trading Period.]
A.2.5.6
The Market Operator shall derive the value of the Dispatch Quantity
(qDuoh(t)), for each Generator Unit, u, which has Priority Dispatch, and which
is non-dispatchable, for each Bid Offer Acceptance, o, in Period, h, as
follows:
(a)
The value shall be equal to the Final Physical Notification Quantity
(qFPNuh(t)) for the Generator Unit, determined in accordance with
paragraph A.2.4.3, for each time in Period, h, where the unit does not
have a Dispatch Instruction applying to it; and
(b)
The Market Operator shall determine the value in accordance with
paragraph A.2.5.3 for each time in respect of which a Dispatch
Instruction applies to the unit.
A.2.5.7
The Market Operator shall derive the Dispatch Quantity (QDuγ) for each
Generator Unit, u, in Imbalance Settlement Period, γ, by integrating the
associated function of time Dispatch Quantity (qDuoγ(t)) reflecting the last
Dispatch Instruction in effect from time to time during the Imbalance
Settlement Period, with respect to time across the Imbalance Settlement
Period.
A.2.5.8
Each System Operator shall submit to the Market Operator the Dispatch
Quantity (qDloh(t)) in respect of each Interconnector, l, which is linked to its
Jurisdiction, for each Bid Offer Acceptance, o, in Period, h.
A.2.5.9
The Dispatch Quantity (qDuoh(t)) for each Interconnector Residual Capacity
Unit and each Interconnector Error Unit, u, for each Bid Offer Acceptance, o,
in Period, h, shall be equal to the Dispatch Quantity of the relevant
Interconnector, l.
A.2.5.10 Each System Operator shall submit to the Market Operator the SO
Interconnector Trade Quantity and Price (in the form of Accepted Bid and
Offer Quantities, QABuoih, QAOuoih, and Bid Offer Price, PBOuβoih) for each
Interconnector Residual Capacity Unit, u, relevant to an Interconnector, l,
which is linked to its Jurisdiction, for each Bid Offer Acceptance, o, for Band,
i, in Period, h, and shall identify for each such Bid Offer Acceptance the
Interconnector, Interconnector Direction, Initiating TSO, TSO counterparty,
Trade Type, Reason Code, and Flags.
A.2.5.11 Each System Operator shall submit to the Market Operator the Outturn
Availability Quantity (qAVAILOuh(t)) in respect of each Generator Unit u,
which is registered within its Jurisdiction.
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A.2.6
Metered Quantity Data
A.2.6.1
Each Meter Data Provider shall submit to the Market Operator the Metered
Quantities (QMuγ, QMvγ, and QMlγ) for each Generator Unit, u, Supplier Unit,
v, and Interconnector, l, as applicable, which is registered within, or linked to,
its Jurisdiction in each Imbalance Settlement Period, γ.
A.2.6.2
The Non-Interval Energy Proportion Factor (FNIEPvγ) is a factor for a
Supplier Unit, v, in an Imbalance Settlement Period, γ, greater than or equal
to zero and less than or equal to one, which represents the proportion of the
Metered Quantity that is in respect of non-Interval Metering.
A.2.6.3
Each Meter Data Provider shall submit to the Market Operator the NonInterval Energy Proportion Factor (FNIEPvγ) for each Supplier Unit, v, which
is registered within its Jurisdiction, in Imbalance Settlement Period, γ .
A.2.6.4
The value of the Metered Quantity (QMuγ) for each Interconnector Error Unit
and each Interconnector Residual Capacity Unit, u, shall be equal to the
Metered Quantity (QMlγ) of the relevant Interconnector, l.
A.2.6.5
The value of the Metered Quantity (QMuγ) for each Generator Unit, u, which
is an Assetless Unit or a Trading Unit, shall be deemed to be zero.
Explanatory Note
The following two paragraphs have been added to enact the treatment of Demand Side
Units in the balancing and imbalance arrangements. A high level overview of the treatment
is as follows:
- It is assumed that the set up for a DSU will be based on at least 2 units on a trading site
(the DSU and a Trading Site Supplier Unit). A DSU could participate in the ex-ante
markets, and would submit a PN, COD and TOD (in accordance with the Data Submission
section) to the balancing market like a Generator Unit with a positive output range.
-
Make QM for the DSU = QD (assume they met their required dispatch);
-
Make QM for the associated TSSU = -QD.
This would have the following outcomes:
- If a DSU achieves an ex-ante market position, submit a PN, and they are run to that
position, there will be no incs/decs, and with QM = QD, they will be deemed in balance, so
no BM settlement on the DSU. The associated TSSU would have QM = -QD, and with
QEX = 0, they would be deemed in imbalance, and would pay back the DSU’s ex-ante
position through the imbalance price.
- If a DSU is inc’d, it is assumed they have delivered and therefore they would receive
the imbalance price and potentially a premium. The associated TSSU would pay back this
inc volume at the imbalance price only.
- If the DSU is dec’d, it is assumed they have delivered, therefore they would pay back at
the imbalance price or get a discount for this amount if applicable. The QM = -QD on the
associated TSSU would not reflect the DSU’s dec volume, as the dec means that a
reduction in the demand (and the benefit thereof which would have been accounted for on
a separate Supplier Unit) did not materialise, therefore there would be no settlement of the
dec volume through the TSSU to remove the benefit from the DSU.
The net result of this treatment is that the benefit of materialised demand reductions, which
would be accounted for on a separate Supplier Unit at the Imbalance Price, is removed
from the Demand Side Unit to ensure against double-counting.
A.2.6.6
The value of the Metered Quantity (QMuγ) for each Generator Unit, u, which
is a Demand Side Unit, shall be deemed to be equal to the Dispatch Quantity
(QDuγ) of that Demand Side Unit.
A.2.6.7
The value of the Metered Quantity (QMvγ) for each Trading Site Supplier
Unit, v, which is on a Trading Site, s, associated with a Generator Unit, u,
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which is a Demand Side Unit, shall be deemed to be equal to the negative of
the Dispatch Quantity (QDuγ) of that Demand Side Unit.
A.2.7
Timing Conventions
A.2.7.1
A time is deemed to be an instant in time, and to have no duration.
A.2.7.2
The Trading Period for the balancing market is the period of time relevant to
the trading of energy in the balancing market. It is defined in [section from
Data Submission]. It is represented by the subscript for a generalised period,
h.
A.2.7.3
The Intraday Trade Duration is the period relevant to the trading of energy in
the intraday market, which is the period covered by a product in the intraday
market. It can vary depending on the products in the market[, as defined in
NEMO rules], and are assumed for the calculations in this Chapter to be
either one hour or thirty minutes. It is represented by the subscript for a
generalised period, h.
A.2.7.4
The Day-ahead Trade Duration for a day-ahead market trade is the period
relevant to the trading of energy in the day-ahead market, which is the period
covered by a traded product in the day-ahead market. It can vary depending
on the products in the market[, as defined in NEMO rules], and are assumed
for the calculations in this Chapter to be either one hour or thirty minutes. It is
represented by the subscript for a generalised period, h.
A.2.7.5
The Imbalance Pricing Period is the period within an Imbalance Settlement
Period relevant to the calculations for the execution of the Imbalance Pricing
Process. It is defined in [section on Imbalance Pricing]. It is represented by
the subscript φ.
A.2.7.6
The Imbalance Settlement Period is a thirty minute period beginning on each
hour or half hour. It is represented by the subscript γ.
A.2.7.7
The Aggregated Settlement Period is the period relevant to the calculation of
imbalance quantities covering one or multiple Imbalance Settlement Periods
for the execution of the Imbalance Settlement Process. It is represented by
the subscript α.
A.2.7.8
The Intraday Interconnector Trade Duration is the period relevant to the
scheduling of energy flows on interconnectors in the intraday market. It is
assumed for the calculations in this chapter to be thirty minutes. It is
represented by the subscript for a generalised period, h.
A.3
DETERMINATION OF TIMES AND RELEVANT COMMERCIAL
OFFER DATA FOR BID OFFER ACCEPTANCES
A.3.1
Times Relevant to Bid Offer Acceptances
Explanatory Note
Changes made to this section reflect changes to how the Instruction Profiling functionality
is expected to work. It is intended that instruction profiles would be created for each
Dispatch Instruction which are the physical instructions issued by the System Operators,
and also Pseudo-Dispatch Instructions, which are settlement constructs in order to have
closed acceptances of open instructions. Therefore every BOA would result from a DI,
either a physical one, or a pseudo one. Definitions on when a Pseudo-Dispatch Instruction
is created, what constitutes its “effective time” and “issue time”, will be outlined in the
instruction profiling section.
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A.3.1.1
The Market Operator shall determine the Bid Offer Acceptance Time for each
Bid Offer Acceptance, o, to be the Instruction Issue Time of the Dispatch
Instruction relevant to the Dispatch Quantity (qDuoh(t)) for the Bid Offer
Acceptance as defined in [the section on Instruction Profiling].
A.3.1.2
The Market Operator shall determine the Bid Offer Opening Time for each
Bid Offer Acceptance, o, to be the Instruction Effective Time of the Dispatch
Instruction relevant to the Dispatch Quantity (qDuoh(t)) for the Bid Offer
Acceptance as defined in [the section on Instruction Profiling].
A.3.2
Commercial Offer Data Format for Settlement Calculations
A.3.2.1
For the purposes of the Settlement process, the Market Operator shall, for
each Generator Unit, u, and for each period, h, derive a set of Price Quantity
Pairs comprising a single set of Quantities each having two prices applicable
(an Incremental Price and a Decremental Price), from the individual
Incremental and Decremental Price Quantity Pairs (Puih and quih), submitted
by each Participant through its Commercial Offer Data in accordance with
[section in Data Submission], as follows:
A.3.2.2
A.3.2.3
(a)
The Quantities (quih) for the single set of Price Quantity pairs shall be
the Quantities in each Incremental and Decremental Price Quantity
pair submitted by the Participant, ranked in order of increasing
Quantity value, and assigned in this order a Band index, i. For
positive Quantity values, the Band index, i, shall increase from zero
with every Quantity increasing from zero. For negative Quantity
values, the Band index, i, shall decrease from zero with every
Quantity decreasing from zero;
(b)
The Incremental Price (PINCuih) for the Quantity (quih) in the single set
of Price Quantity pairs shall be the Price from the Incremental Price
Quantity Pair applicable at that Quantity. The Decremental Price
(PDECuih) for the Quantity (quih) in the single set of Price Quantity
Pairs shall be the Price from the Decremental Price Quantity pair
applicable at that Quantity.
The Market Operator shall derive the Bid Offer Upper Range Quantity
(qBOURuih(t)) and Bid Offer Lower Range Quantity (qBOLRuih(t)) for each
Generator Unit, u, for each Band, i, in each Period, h, from the sets of Price
Quantity Pairs derived under paragraph A.3.2.1, as follows:
(a)
The Bid Offer Upper Range Quantity (qBOURuih(t)) will be equal to the
Quantity (quih) for the relevant Price Quantity pair derived under
paragraph A.3.2.1, for Band, i, where i ≥ 0;
(b)
The Bid Offer Lower Range Quantity (qBOLRuih(t)) will be equal to the
Quantity (quih) for the relevant Price Quantity pair derived under
paragraph A.3.2.1, for Band, i, where i ≤ 0.
The Market Operator shall derive the Bid Offer Price (PBOuih) for each
Generator Unit, u, for each Band, i, in each Period, h, from the single set of
Price Quantity pairs derived under paragraph A.3.2.1, as follows:
(a)
If the quantity to which the Bid Offer Price applies has a positive
value, the Bid Offer Price shall be the PINCuih of the relevant Price
Quantity pair;
(b)
If the quantity to which the Bid Offer Price applies has a negative
value, the Bid Offer Price shall be the PDECuih of the relevant Price
Quantity pair.
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A.3.2.4
The value of the Bid Offer Price (PBOuih) for a Generator Unit, u, which has
Priority Dispatch, which is non-dispatchable, and which has zero variable
costs, for Band, i, in Period, h, shall be deemed to be zero if the quantity to
which the Bid Offer Price applies is negative, with the exception of when the
quantity considered is a Bid Price Only Accepted Bid Quantity in accordance
with section A.7.
A.3.3
Commercial Offer Data to be Used
Explanatory Note
Commercial Bid Offer Data submitted in accordance with the paper on Balancing Market
Data Submission must be provided in Complex Bid Offer Data Format and may also be
provided in Simple Bid Offer Data Format.
Extra text has been added here to give effect to the market power decision. An additional
test for the Market Power Condition is added to determine which COD set should be used
in the calculation of balancing market quantities, and the determination of the prices of
those quantities, for Settlement processes. If the Market Power Condition is true, then the
Complex COD, which outside of the TSC rules would have a Bidding Code of Practice
apply to it, would be used.
The Market Power condition is to determine whether the unit is “non-energy” using the
results of the Imbalance Pricing Flagging and Tagging process. There are two aspects of
the Flagging and Tagging process which determine whether or not a unit is non-energy:
-
The System Operator flag, which determines if a unit is at a certain output level
due to a system constraint and is therefore non-energy; and
-
The NIV Tag, which determines that a unit is non-energy in the absence of
sufficient System Operator flagged actions being tagged out to meet the NIV (i.e.
if there are more unflagged actions than the NIV, additional actions are tagged out
and in this way are deemed to be non-energy).
If a unit is found to be either flagged or tagged (fully or partially), it is deemed to be nonenergy in that period for the purposes of the Market Power decision. A unit is SO flagged if
the flag is set to zero. The unit is NIV tagged if the tag variable is set to anything other than
a value of one. Therefore the product of these would have to be equal to one for the unit to
not be flagged or tagged, meaning that the Market Power conditions apply if the value of
the product is less than one.
Using both the Flag and Tag elements also ensures the market power conditions are
robust so that if changes to the SO Flagging approach were to be taken and more
emphasis given to NIV tagging approaches, then the Market Power conditions would still
apply to those units deemed to be non-energy under the NIV tagging approach.
A.3.3.1
A.3.3.2
For the purposes of calculating the Imbalance Price in an Imbalance Pricing
Period, φ, in calculating Accepted Bid Quantity and Accepted Offer Quantity,
and determining the relevant Bid Offer Price, in respect of a Bid Offer
Acceptance, the Market Operator shall use the following Commercial Offer
Data:
(a)
If the Bid Offer Acceptance Time is before the Gate Closure for the
Imbalance Settlement Period containing the Bid Offer Opening Time,
the most recently submitted valid Complex Bid Offer Format Data for
the relevant Trading Day as at the Bid Offer Acceptance Time;
(b)
Otherwise, the most recently submitted valid Simple Bid Offer Format
Data for the relevant Imbalance Settlement Period as at the Bid Offer
Acceptance Time.
For the purposes of calculating settlement quantities in an Imbalance
Settlement Period, γ, in calculating Accepted Bid Quantity and Accepted
Offer Quantity, and determining the relevant Bid Offer Price, in respect of a
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Bid Offer Acceptance, the Market Operator shall use the following
Commercial Offer Data:
(a)
If the Bid Offer Acceptance Time is before the Gate Closure for the
Imbalance Settlement Period containing the Bid Offer Opening Time,
the most recently submitted valid Complex Bid Offer Format Data for
the relevant Trading Day as at the Bid Offer Acceptance Time;
(b)
If any Bid Offer Acceptance for Generator Unit, u, at rank, k, has,
after applying the Flagging and Tagging process in accordance with
[section on Imbalance Pricing], a Net Imbalance Volume Tag
(TNIVukφ) with a value less than one, or a System Operator Flag
(FSOukφ) with a value less than one, for any Imbalance Pricing Period,
φ, within the Imbalance Settlement Period, γ, the most recently
submitted valid Complex Bid Offer Format Data for the relevant
Trading Day as at the Bid Offer Acceptance Time.
where:
(c)
A.3.3.3
A.3.3.4
(i)
FSOukφ is the System Operator Flag for Generator Unit, u, and
rank, k, in Imbalance Pricing Period, φ, determined in
accordance with [section on Imbalance Pricing] and where in
the absence of a value for the period resulting from the
process outlined in [Section on Imbalance Pricing] a value of
one will be used; and
(ii)
TNIVukφ is the value of the Net Imbalance Volume Tag for
Generator Unit, u, and rank, k, in Imbalance Pricing Period, φ,
determined in accordance with [section on Imbalance Pricing]
and where in the absence of a value for the period resulting
from the process outlined in [Section on Imbalance Pricing] a
value of one will be used.
Otherwise, the most recently submitted valid Simple Bid Offer Format
Data for the Imbalance Settlement Period as at the Bid Offer
Acceptance Time.
Where in accordance with paragraphs A.3.3.1 or A.3.3.2 the Market Operator
is required to use Complex Bid Offer Format Data, it shall use the following
Commercial Offer Data for each Imbalance Settlement Period relevant to the
Bid Offer Acceptance:
(a)
The Trading Day Specific Complex Bid Offer Format Data (if any) that
was valid for the Imbalance Settlement Period containing the Bid
Offer Opening Time most recently submitted as at the Bid Offer
Acceptance Time; or
(b)
Otherwise, the valid Default Complex Bid Offer Format Data that had
been most recently submitted as at the Bid Offer Acceptance Time.
Where in accordance with paragraphs A.3.3.1 or A.3.3.2 the Market Operator
is required to use Simple Bid Offer Format data, it shall use the following
Commercial Offer Data for each Imbalance Settlement Period relevant to the
Bid Offer Acceptance:
(a)
The Trading Period Specific Simple Bid Offer Format Data (if any)
that was valid for the Imbalance Settlement Period relevant to the Bid
Offer Acceptance and had been most recently submitted as at the Bid
Offer Acceptance Time; or
11
(b)
A.4
Otherwise, the Price Quantity pair data of the Complex Bid Offer
Format Data that it would be required to use in accordance with
paragraph A.3.3.3(a) or A.3.3.3(b), as applicable, were that
paragraph to apply.
TRADING BOUNDARY AND TREATMENT OF LOSSES
Explanatory Note
Functionality for applying the loss adjustment factors to the variables.
A.4.1
Trading Boundary
Explanatory Note
The provisions on the Trading Boundary are similar to that in the SEM TSC in that activity is
deemed to take place at the boundary, necessitating the application of loss factors. Text from
the TSC has been removed to reflect the differences between the SEM and the Balancing
Market:
-
The SEM is a Pool, and reflects a single volume of all generation being sold, and all
consumption being bought;
-
In the Balancing Market the volumes reflect differences between ex-ante market
volumes bought and sold, the balancing market volumes bought and sold, and actual
outturn generation, consumption or imbalance of different units. It no longer suffices
to think in terms of all units delivering energy being bought by all units taking energy.
For example, a negative imbalance may not be “taking energy” but rather a reduction
in the amount of energy being delivered.
A definition of Trading Boundary would be provided as part of the Glossary, and would be
similar to that in the SEM. An example is provided in the first paragraph below.
A.4.1.1
The Trading Boundary is a notional boundary between all points on the
Transmission System and all points on the Distribution System. The Trading
Boundary is the notional balancing point for generation and supply and is the
point of sale for trading in the SEM at which the title for all products and
services settled through the trading arrangements set out in the Code
transfers. All volumes traded or settled at the Trading Boundary are adjusted,
where required, to reflect Transmission Losses and (where applicable)
Distribution Losses. For the avoidance of doubt, for all Supplier Units or
Generator Units that are Distribution Connected, the Trading Boundary is not
the specific boundary between the Transmission System and Distribution
System for that Unit and so appropriate Combined Loss Adjustment Factors
also apply to volumes associated with these Units in order to ensure that
they are appropriately adjusted for Transmission Losses and Distribution
Losses incurred as electricity is transported to (or from) the Trading
Boundary from (or to) the relevant boundary of the Transmission System and
the Distribution System for that Unit and then from (or to) the point of
connection of that Unit.
A.4.1.2
Before submitting to the Market Operator Meter Data relating to a Generator
Unit (other than a Demand Side Unit), or a Supplier Unit, that is Distribution
Connected and for which the Distribution System Operator provides the
Metered Quantity data, each Distribution System Operator shall apply the
appropriate Distribution Loss Adjustment Factor to the Meter Data values.
12
A.4.2
Setting of Loss Adjustment Factors
A.4.2.1
At least [four months] before the start of each Tariff Year, each System
Operator shall submit to the Regulatory Authorities a set of Transmission
Loss Adjustment Factors for each Generator Unit, other than a Demand Side
Units, that is Connected within its Jurisdiction and for each Interconnector
linked to that Jurisdiction, calculated in co-operation with the System
Operator in the other Jurisdiction and in accordance with the statutory and
Licence requirements pertaining within its Jurisdiction, for each Imbalance
Settlement Period in the Tariff Year. The Transmission Loss Adjustment
Factors for each Interconnector shall be applicable to each Interconnector
Error Unit and Interconnector Residual Capacity Unit registered to the
relevant Interconnector.
A.4.2.2
In determining Transmission Loss Adjustment Factors the System Operator
shall incorporate Transmission Losses incurred on the relevant
Interconnector as estimated in consultation with the Interconnector Owner.
A.4.2.3
The System Operator shall incorporate the estimated Transmission Losses
incurred on the Interconnector into the Transmission Loss Adjustment
Factors having regard to its expectation of the pre-dominant direction of flow
on the Interconnector in the relevant Trading Period.
A.4.2.4
At least [three months] before the start of each Tariff Year, each Distribution
System Operator shall provide the relevant System Operator with a set of
Distribution Loss Adjustment Factors for each Generator Unit (other than
Demand Side Units) that is Distribution Connected within its Jurisdiction,
calculated in accordance with the statutory and Licence requirements
pertaining within its Jurisdiction, for each Imbalance Settlement Period in the
Tariff Year, and including the relevant supporting information to enable the
System Operator to calculate the corresponding Combined Loss Adjustment
Factors.
A.4.2.5
At least [two months] before the start of each Tariff Year, or within [five
Working Days] of its receipt from the Regulatory Authorities, whichever is
later, each System Operator shall provide to the Market Operator [in
accordance with Appendix K “Market Data Transactions” ]the System
Parameters Data Transaction which shall comprise a complete set of
Combined Loss Adjustment Factors for each Generator Unit (other than
Demand Side Units, Interconnector Error Units or Interconnector Residual
Capacity Units) Connected within its Jurisdiction, and each Interconnector
linked to that Jurisdiction, for each Imbalance Settlement Period in that Tariff
Year.
A.4.2.6
At least [two months] before the start of each Tariff Year, or within [five
Working Days] of its receipt from the Regulatory Authorities, whichever is
later, each System Operator shall provide the Market Operator with a
complete set of Transmission Loss Adjustment Factors for each Generator
Unit (other than Demand Side Units) that is Connected within its Jurisdiction
for each Imbalance Settlement Period in that Tariff Year in accordance with
those prepared and submitted to the Regulatory Authorities under paragraph
A.4.2.1.
A.4.2.7
At least [two months] before the start of each Tariff Year each System
Operator shall provide the Market Operator with a complete set of
Distribution Loss Adjustment Factors for each Generator Unit (other than
Demand Side Units) that is Distribution Connected within its Jurisdiction for
each Imbalance Settlement Period in that Tariff Year.
13
A.4.2.8
The Market Operator shall publish the approved Combined Loss Adjustment
Factor value(s) within [5 Working Days] of receipt of the System Parameters
Data Transaction.
A.4.2.9
The Market Operator shall publish the approved Distribution Loss Adjustment
Factor value(s) and Transmission Loss Adjustment Factor value(s) within [5
Working Days] of receipt of the Loss Adjustment Factors Data Transaction.
A.4.2.10 The Transmission Loss Adjustment Factor (FTLAFvγ) shall be equal to 1 for
each Supplier Unit, v.
A.4.2.11 The Combined Loss Adjustment Factor (FCLAFuγ) for each Generator Unit,
u, in Imbalance Settlement Period, γ, shall be calculated by the relevant
System Operator as follows:
𝐹𝐶𝐿𝐴𝐹𝑢𝛾 = 𝑅𝑜𝑢𝑛𝑑(𝐹𝑇𝐿𝐴𝐹𝑢𝛾 × 𝐹𝐷𝐿𝐴𝐹𝑢𝛾 )
where:
(a)
Round(x) is a function that rounds x to 3 decimal places;
(b)
FTLAFuγ is the Transmission Loss Adjustment Factor for Generator
Unit, u, in Imbalance Settlement Period, γ; and
(c)
FDLAFuγ is the Distribution Loss Adjustment Factor for Generator
Unit, u, in Imbalance Settlement Period, γ. In cases where a
Distribution Loss Adjustment Factor has been applied to a variable in
advance of data submission in accordance with paragraph A.4.1.2, a
value of one for the Distribution Loss Adjustment Factor shall be used
for the calculation of the Combined Loss Adjustment Factor to be
applied to that variable.
A.4.2.12 The Combined Loss Adjustment Factor (FCLAFvγ) for each Supplier Unit, v,
in Imbalance Settlement Period, γ, shall be set equal to 1.
A.4.2.13 The Combined Loss Adjustment Factor (FCLAFuγ) for each Demand Side
Unit, u, in Imbalance Settlement Period, γ, shall be set equal to 1.
A.4.3
Application of Loss Adjustment Factors
Explanatory Note
Intention of equations in this section are:
-
-
A.4.3.1
For internal participants, apply combined loss adjustment factor to any variable
desired, signified throughout the document by the use of the term “Loss-Adjusted”
and an “LF” in the variable name;
For cross border variables, apply the factor like above if a positive value (i.e.
exporting), but apply the reciprocal (1 / factor) if a negative value (i.e. importing).
In these rules, terms finishing LF have the loss factor applied in that calculation as if
the original term were multiplied by the applicable loss factor in that calculation. Other
terms may be defined from data that has already been loss factor adjusted so do not
have LF at the end of the term as no further loss factor adjustment is required. These
differences arise as a result of calculations which involve both ex-ante market
transactions (which are loss factor adjusted at submission and require no further
adjustment) and balancing market transactions (which must be explicitly loss factor
adjusted in settlement).
In this Code, the term ‘Loss-Adjusted’ applied to any variable, or the
inclusion of the letters ‘LF’ at the end of any variable term, denotes that a
value is to be calculated at the Trading Boundary, through application of the
14
relevant Combined Loss Adjustment Factor as determined under paragraph
A.4.2.11.
A.4.3.2
Where the Market Operator is required to calculate or determine a LossAdjusted variable which relates to a Generator Unit, u, other than an
Interconnector Error Unit or an Interconnector Residual Capacity Unit, and
each Supplier Unit, v, in respect of an Imbalance Settlement Period, γ, and
where XXXγ is the variable before the application of Transmission Losses
and Distribution Losses, it shall apply the following calculation:
𝑋𝑋𝑋𝐿𝐹𝛾 = 𝑋𝑋𝑋𝛾 × 𝐹𝐶𝐿𝐴𝐹𝛾
where:
A.4.3.3
(a)
XXXLFγ is the relevant Loss-Adjusted variable to be determined; and
(b)
FCLAFγ is the Combined Loss Adjustment Factor for Generator Unit,
u, or Supplier Unit, v, in Imbalance Settlement Period, γ, determined
under paragraph A.4.2.11.
Where the Market Operator is required to calculate a Loss-Adjusted variable
which relates to an Interconnector Error Unit or Interconnector Residual
Capacity Unit, in respect of an Imbalance Settlement Period, γ, and where
XXXuγ is the variable before application of Transmission Losses and
Distribution Losses, it shall apply the following calculation:
𝐼𝑓 𝑋𝑋𝑋 ≥ 0 𝑡ℎ𝑒𝑛
𝑋𝑋𝑋𝐿𝐹𝑢𝛾 = 𝑋𝑋𝑋𝑢𝛾 × 𝐹𝐶𝐿𝐴𝐹𝑙𝛾
𝑒𝑙𝑠𝑒
𝑋𝑋𝑋𝑢𝛾
𝑋𝑋𝑋𝐿𝐹𝑢𝛾 =
𝐹𝐶𝐿𝐴𝐹𝑙𝛾
where:
A.5
(a)
XXXLFuγ is the relevant Loss-Adjusted variable to be determined; and
(b)
FCLAFlγ is the Combined Loss Adjustment Factor for the relevant
Interconnector, l, in Imbalance Settlement Period, γ, determined
under paragraph A.4.2.11.
IMBALANCE COMPONENT PAYMENTS AND CHARGES
Explanatory notes
-
Imbalance Component: Applies the imbalance settlement price to any difference
between the ex-ante volumes procured and the metered volumes delivered. Includes
instructed imbalances from dispatch instructions (implements part of decision to
remunerate these at the better of the imbalance settlement price or the bid/offer price,
rest of implementation through premium/discount component), and uninstructed
imbalances from PN submission, underdelivery or overdelivery.
-
The balancing market will commence with a half hourly trading/imbalance settlement
period. The ex-ante markets offer hourly period products. Therefore since imbalance
quantities are the difference between metered quantities and ex-ante contracted
quantities, and ex-ante contract quantities will apply to periods longer than the
imbalance settlement period, the determination of imbalances for each imbalance
settlement period requires some form of allocation of ex-ante contract quantities to
those shorter periods.
15
A.5.1
Setting of Imbalance Payment Parameters
A.5.1.1
If requested by the Regulatory Authorities, the [Market Operator] shall report
to the Regulatory Authorities proposing the following parameters to be used
in the calculation of Imbalance Payments and Charges for that Year:
(a)
The value, or description of the methodology for determining the
value, of the Imbalance Weighting Factor (WFIMBγ) in each
Imbalance Settlement Period, γ, for Year, y.
A.5.1.2
The [Market Operator's] report must set out any relevant research or analysis
carried out by the Market Operator and the justification for the specific
values, or sources for values, or methodology proposed. The report may,
and shall if so requested by the Regulatory Authorities, include alternative
values or methodologies from those proposed and must set out the
arguments for and against such alternatives.
A.5.1.3
The Market Operator shall publish the approved value for, or methodology
for determining, the parameter referred to in paragraph A.5.1.1, and the date
and time on which it comes into effect, within [5 Working Days] of receipt of
the Regulatory Authorities' determination.
A.5.1.4
The duration of the Aggregated Settlement Period, α, shall be the period
determined by the Regulatory Authorities from time to time. The Market
Operator shall publish the approved duration of the Aggregated Settlement
Period within [5 Working Days] of receipt of the Regulatory Authorities’
determination.
A.5.1.5
If the Regulatory Authorities determine a revised duration for the Aggregated
Settlement Period, α, under paragraph A.5.1.4, the revised duration takes
effect at a time specified by the Regulatory Authorities in their determination
(which must not be earlier than [six Months] from the date of the
determination).
A.5.2
Calculation of Ex-Ante Quantities
Explanatory Note
Intention of the equation below is as follows:
-
Calculate the imbalance over the Aggregated Settlement Period if it was greater
than the Imbalance Settlement Period (AGSP envisaged to be the same as the ISP
at first, but could be moved to 1 hour if required in future) between products with
trading periods of greater than ISP length, and the metered quantities, and weight
this imbalance into each Imbalance Settlement Period (half hour);
-
When this imbalance in each ISP is taken away from the metered quantity in that
ISP, it results in the split of the ex-ante quantity for the products considered into
each ISP.
-
If the imbalance is calculated over the Imbalance Settlement Period rather than the
Aggregated Settlement Period, then any products with length greater than ISP will
be split into equal proportions into each ISP.
-
The ex-ante products with trading periods of half an hour are then directly added
onto the split-up ex-ante quantity, giving the total ex-ante quantity in that ISP.
-
Also need to build into equation the removal of averaging if no ASP-granular
products are traded in a period. E.g. if there is no day-ahead or hour trading period
intraday products traded, and the unit has only traded half-hour granular products,
and the imbalance settlement period is half an hour, QEX should only be equal to
the sum of the half-hour granular products, rather than also considering a split of
the imbalances against non-existant hourly products. Instead of the FIMBAVG
16
component which was previously introduced, this is now done with logical
statements where different calculations are done depending on if the hourly
products have been traded by a unit or not.
A.5.2.1
When the Aggregated Settlement Period Duration is shorter than or equal to
the Imbalance Settlement Period Duration, the provisions in paragraphs
A.5.2.2 to A.5.2.5 shall apply.
A.5.2.2
For each Day-ahead Trade Quantity (QTDAxh) and Intraday Trade Quantity
(QTIDxh) which has a Trade Duration longer than the Imbalance Settlement
Period Duration, the Market Operator shall calculate the quantity of each
Trade, x, for each Supplier Unit, v, and each Generator Unit, u, other than an
Interconnector Error Unit or Interconnector Residual Capacity Unit, to be
allocated into each Imbalance Settlement Period, γ, as follows:
𝑄𝑇𝐷𝐴𝑥𝛾 = 𝑄𝑇𝐷𝐴𝑥ℎ ×
𝑄𝑇𝐼𝐷𝑥𝛾 = 𝑄𝑇𝐼𝐷𝑥ℎ ×
𝐷𝐼𝑆𝑃
𝐷𝑇𝐷𝐴𝑥
𝐷𝐼𝑆𝑃
𝐷𝑇𝐼𝐷𝑥
where:
A.5.2.3
(a)
QTDAxh is the Day-ahead Trade Quantity for Trade, x, for Generator
Unit, u, or Supplier Unit, v, in Day-ahead Trading Period, h;
(b)
QTIDxh is the Intraday Trade Quantity for Trade, x, for Generator Unit,
u, or Supplier Unit, v, in Intraday Trading Period, h;
(c)
DISP is the Imbalance Settlement Period Duration;
(d)
DTDAx is the Day-ahead Trade Duration of Trade, x; and
(e)
DTIDx is the Intraday Trade Duration of Trade, x.
The Market Operator shall calculate the Ex-Ante Quantity (QEXγ) for each
Supplier Unit, v, and each Generator Unit, u, other than an Interconnector
Error Unit or Interconnector Residual Capacity Unit, in each Imbalance
Settlement Period, γ, as follows:
𝑄𝐸𝑋𝛾 =
∑
𝑄𝑇𝐷𝐴𝑥𝛾 +
𝑥 𝑤ℎ𝑒𝑟𝑒 ℎ>𝛾
+
∑
𝑥 𝑤ℎ𝑒𝑟𝑒 ℎ≤𝛾
∑
𝑄𝑇𝐷𝐴𝑥ℎ +
∑
𝑄𝑇𝐼𝐷𝑥𝛾
𝑥 𝑤ℎ𝑒𝑟𝑒 ℎ>𝛾
𝑄𝑇𝐼𝐷𝑥ℎ
𝑥 𝑤ℎ𝑒𝑟𝑒 ℎ≤𝛾
where:
(a)
QTDAxh is the Day-ahead Trade Quantity for Trade, x, for Generator
Unit, u, or Supplier Unit, v, in Day-ahead Trading Period, h;
(b)
QTIDxh is the Intraday Trade Quantity for Trade, x, for Generator Unit,
u, or Supplier Unit, v, in Intraday Trading Period, h;
(c)
∑𝑥 𝑤ℎ𝑒𝑟𝑒 ℎ>𝛾 means the sum of the quantity for each Trade, x, whose
Trade Duration was greater than the Imbalance Settlement Period
Duration, calculated in accordance with paragraph A.5.2.2; and
17
(d)
A.5.2.4
∑𝑥 𝑤ℎ𝑒𝑟𝑒 ℎ≤𝛾 means the sum of the quantities for each Trades, x,
whose Trade Duration was less than or equal to the Imbalance
Settlement Period Duration.
The Market Operator shall calculate the quantity of the final Intraday
Interconnector Schedule Quantity (QICSIDlh) for each Interconnector, l, to be
allocated into each Imbalance Settlement Period, γ, as follows :
(a)
If the final Intraday Interconnector Schedule Quantity (QICSIDlh) has
an Intraday Interconnector Trade Duration longer than the Imbalance
Settlement Period Duration, then:
𝑄𝐼𝐶𝑆𝐼𝐷𝑙𝛾 = 𝑄𝐼𝐶𝑆𝐼𝐷𝑙ℎ ×
(b)
𝐷𝐼𝑆𝑃
𝐷𝑇𝐼𝐶𝐼𝐷(𝑀𝑖𝑛)
Otherwise:
𝑄𝐼𝐶𝑆𝐼𝐷𝑙𝛾 = ∑ 𝑄𝐼𝐶𝑆𝐼𝐷𝑙ℎ
ℎ≤𝛾
where:
A.5.2.5
(i)
QICSIDlh is the Intraday Interconnector Schedule Quantity for
Interconnector, l, in Intraday Trading Period, h;
(ii)
∑ℎ≤𝛾 means the sum for of the quantities whose Intraday
Interconnector Trade Duration was less than or equal to the
Imbalance Settlement Period Duration;
(iii)
DISP is the Imbalance Settlement Period Duration; and
(iv)
DTICID(Min) is the shortest Intraday Interconnector Trade
Duration offered in the intraday market.
The Market Operator shall calculate the Ex-Ante Quantity (QEXuγ) for each
Generator Unit, u, that is an Interconnector Error Unit or Interconnector
Residual Capacity Unit, in each Imbalance Settlement Period, γ, as follows:
𝑄𝐸𝑋𝑢𝛾 = 𝑄𝐼𝐶𝑆𝐼𝐷𝑙𝛾
where:
(a)
QICSIDlγ is the Intraday Interconnector Schedule Quantity for
Interconnector, l, relevant to the Interconnector Error Unit or
Interconnector Residual Capacity Unit, u, in Imbalance Settlement
Period, γ.
A.5.2.6
When the Aggregated Settlement Period Duration is greater than the
Imbalance Settlement Period Duration, the provisions in paragraphs A.5.2.7
to A.5.2.10 shall apply.
A.5.2.7
For Supplier Units, v, or Generator Units, u, other than an Interconnector
Error Unit or Interconnector Residual Capacity Unit, that do not have any
Day-ahead Trade Quantities or Intraday Trade Quantities with a Trade
Duration longer than the Imbalance Settlement Period Duration, the Market
Operator shall calculate the Ex-Ante Quantity for each of those Generator
18
Units, u, and each of those Supplier Units, v, in each Imbalance Settlement
Period, γ, as follows:
𝑄𝐸𝑋𝛾 =
∑
𝑄𝑇𝐷𝐴𝑥ℎ +
𝑥 𝑤ℎ𝑒𝑟𝑒 ℎ≤𝛾
A.5.2.8
∑
𝑄𝑇𝐼𝐷𝑥ℎ
𝑥 𝑤ℎ𝑒𝑟𝑒 ℎ≤𝛾
(a)
QTDAxh is the Day-ahead Trade Quantity for Trade, x, for Generator
Unit, u, or Supplier Unit, v, in Day-ahead Trading Period, h;
(b)
QTIDxh is the Intraday Trade Quantity for Trade, x, for Generator Unit,
u, or Supplier Unit, v, in Intraday Trading Period, h; and
(c)
∑𝑥 𝑤ℎ𝑒𝑟𝑒 ℎ≤𝛾 means the sum of the quantities for each Trade, x,
whose Trade Duration was less than or equal to the Imbalance
Settlement Period Duration.
For Supplier Units, v, or Generator Units, u, other than an Interconnector
Error Unit or Interconnector Residual Capacity Unit, that have any Dayahead Trade Quantities or Intraday Trade Quantities with a Trade Duration
longer than the Imbalance Settlement Period:
(a)
For each Day-ahead Trade Quantity (QTDAxh) and Intraday Trade
Quantity (QTIDxh) which has a Trade Duration longer than the
Aggregated Settlement Period Duration, the Market Operator shall
calculate the quantity of each Trade, x, for each Supplier Unit, v, and
each Generator Unit, u, to be allocated into each Aggregated
Settlement Period, α, as follows:
𝑄𝑇𝐷𝐴𝑥𝛼 = 𝑄𝑇𝐷𝐴𝑥ℎ ×
𝑄𝑇𝐼𝐷𝑥𝛼 = 𝑄𝑇𝐼𝐷𝑥ℎ ×
(b)
𝐷𝐴𝐺𝑆𝑃
𝐷𝑇𝐷𝐴𝑥
𝐷𝐴𝐺𝑆𝑃
𝐷𝑇𝐼𝐷𝑥
The Market Operator shall calculate the Ex-Ante Quantity (QEXγ) for
each Supplier Unit, v, and each Generator Unit, u, in each Imbalance
Settlement Period, γ, as follows:
𝑄𝐸𝑋𝛾 =
𝑄𝑀𝐿𝐹𝛾
(
−
𝑊𝐹𝐼𝑀𝐵𝛾
(( ∑ 𝑄𝑀𝐿𝐹𝛾 )
∑𝑎𝑙𝑙 𝛾 ∈ 𝛼 𝑊𝐹𝐼𝑀𝐵𝛾
𝑎𝑙𝑙 𝛾 ∈ 𝛼
− (
∑
𝑄𝑇𝐷𝐴𝑥ℎ +
𝑥 𝑤ℎ𝑒𝑟𝑒 ℎ= 𝛼
∑
𝑄𝑇𝐼𝐷𝑥ℎ ))
𝑥 𝑤ℎ𝑒𝑟𝑒 ℎ= 𝛼
)
+
∑
𝑄𝑇𝐷𝐴𝑥ℎ +
𝑥 𝑤ℎ𝑒𝑟𝑒 ℎ≤ 𝛾
∑
𝑥 𝑤ℎ𝑒𝑟𝑒 ℎ≤ 𝛾
19
𝑄𝑇𝐼𝐷𝑥ℎ
where:
A.5.2.9
(i)
DAGSP is the Aggregated Settlement Period Duration;
(ii)
DTDAx is the Day-ahead Trade Duration of Trade, x; and
(iii)
DTIDx is the Intraday Trade Duration of Trade, x.
(iv)
QTIDxh is the Intraday Trade Quantity for Trade, x, for Supplier
Unit, v, or Generator Unit, u, in the Intraday Trade Period, h,
relevant to Trade x;
(v)
QTDAxh is the Day-ahead Trade Quantity for Trade, x, for
Supplier Unit, v, or Generator Unit, u, in the Day-ahead Trade
Period, h relevant to Trade x;
(vi)
WFIMBγ is the Imbalance Weighting Factor for Imbalance
Settlement Period, γ;
(vii)
QMLFγ is the Loss-Adjusted Metered Quantity for Supplier
Unit, v, or Generator Unit, u, in Imbalance Settlement Period,
γ;
(viii)
∑𝑥 𝑤ℎ𝑒𝑟𝑒 ℎ= 𝛼 means the sum of the quantities for each Trade,
x, from the day-ahead market or the intraday market, as the
case may be within whose Day-ahead Trade Period or
Intraday Trade Period, h, as the case may be, the Aggregated
Settlement Period, α, falls in whole or in part; and whose Dayahead Trade Duration or Intraday Trade Duration, as the case
may be, is no shorter than the Aggregated Settlement Period
Duration; and
(ix)
∑𝑥 𝑤ℎ𝑒𝑟𝑒 ℎ≤ 𝛾 means the sum of the quantities for each Trades,
x, whose Trade Duration was less than or equal to the
Imbalance Settlement Period Duration to the extent that the
same Trade has not already been included in the summation
set out in paragraph A.5.2.8(b)(viii).
For Interconnectors, l, that do not have a final Intraday Interconnector
Schedule Quantity with a Trade Duration longer than the Imbalance
Settlement Period Duration, the Market Operator shall calculate the Ex-Ante
Quantity for each Generator Unit, u, which is an Interconnector Error Unit
and an Interconnector Residual Capacity Unit, relevant to Interconnector, l, in
each Imbalance Settlement Period, γ, as follows:
𝑄𝐸𝑋𝑢𝛾 = ∑ 𝑄𝐼𝐶𝑆𝐼𝐷𝑙ℎ
ℎ≤𝛾
where:
(a)
QICSIDlh is the Intraday Interconnector Schedule Quantity for
Interconnector, l, relevant to the Interconnector Error Unit or
Interconnector Residual Capacity Unit, u, in Intraday Trade Period, γ;
and
(b)
∑ℎ≤𝛾 means the sum for of the quantities whose Intraday
Interconnector Trade Duration was less than or equal to the
Imbalance Settlement Period.
20
A.5.2.10 For Interconnectors, l, that have a final Intraday Interconnector Schedule
Quantity with an Intraday Interconnector Trade Duration longer than the
Imbalance Settlement Period Duration:
(a)
The Market Operator shall calculate the quantity of the final Intraday
Interconnector Schedule Quantity (QICSIDlh) for each Interconnector,
l, to be allocated into each Aggregated Settlement Period, α, as
follows:
𝑄𝐼𝐶𝑆𝐼𝐷𝑙𝛼 = 𝑄𝐼𝐶𝑆𝐼𝐷𝑙ℎ ×
(b)
𝐷𝐴𝐺𝑆𝑃
𝐷𝑇𝐼𝐶𝐼𝐷(𝑀𝑖𝑛)
The Market Operator shall calculate the Ex-Ante Quantity (QEXuγ) for
each Generator Unit, u, which is an Interconnector Error Unit and an
Interconnector Residual Capacity Unit, relevant to Interconnector, l, in
each Imbalance Settlement Period, γ, as follows:
𝑄𝐸𝑋𝑢𝛾 =
𝑄𝑀𝐿𝐹𝑙𝛾
(
−
𝑊𝐹𝐼𝑀𝐵𝛾
(( ∑ 𝑄𝑀𝐿𝐹𝑙𝛾 )
∑𝑎𝑙𝑙 𝛾 ∈ 𝛼 𝑊𝐹𝐼𝑀𝐵𝛾
𝑎𝑙𝑙 𝛾 ∈ 𝛼
− (
∑
𝑄𝐼𝐶𝑆𝐼𝐷𝑙ℎ ))
𝑤ℎ𝑒𝑟𝑒 ℎ= 𝛼
+
∑
𝑄𝐼𝐶𝑆𝐼𝐷𝑙ℎ
𝑤ℎ𝑒𝑟𝑒 ℎ≤ 𝛾
)
where:
(i)
QICSIDlh is the Intraday Interconnector Schedule Quantity for
Interconnector, l, in Intraday Trading Period, h;
(ii)
DAGSP is the Aggregated Settlement Period Duration;
(iii)
DTICID(Min) is the shortest Intraday Interconnector Trade
Duration offered in the intraday market.
(iv)
QICSIDlh is the Intraday Interconnector Schedule Quantity for
Interconnector, l, in Intraday Trading Period, h;
(v)
WFIMBγ is the Imbalance Weighting Factor for Imbalance
Settlement Period, γ;
(vi)
QMLFlγ is the Loss-Adjusted Metered Quantity
Interconnector, l, in Imbalance Settlement Period, γ;
(vii)
∑𝑤ℎ𝑒𝑟𝑒 ℎ= 𝛼 means the sum of the quantities within whose
Intraday Trade Period, h, the Aggregated Settlement Period,
α, falls in whole or in part; and whose Intraday Interconnector
Trade Duration, is no shorter than the Aggregated Settlement
Period Duration; and
21
for
(viii)
∑𝑤ℎ𝑒𝑟𝑒 ℎ= 𝛾 means the sum for of the quantities whose
Intraday Interconnector Trade Duration was less than or equal
to the Imbalance Settlement Period Duration to the extent that
the same Trade has not already been included in the
summation set out in paragraph A.5.2.10(b)(vii).
A.5.2.11 The Ex-Ante Quantities (QEXγ) calculated in Section A.5.2 shall, for the
purposes of further uses in this Chapter, be read as QEXuγ where it relates to
a quantity for a Generator Unit, and be read as QEXvγ where it relates to a
quantity for a Supplier Unit.
A.5.3
Calculation of Imbalance Component Payments or Charges
Explanatory Note
Intention of the equation below is as follows:
A.5.3.1
-
Apply the imbalance settlement price to all imbalances in the imbalance settlement
period.
-
This is done by applying it to the difference between what the unit actually did
(metered) and what it wanted to do according to the ex-ante markets (QEX). This
imbalance volume includes the (delivered amounts of) uninstructed imbalance
(difference between metered level and dispatched level), instructed imbalance
(difference between dispatched level and PN’d level) and notified imbalance
(difference between PN’d level and ex-ante market level).
-
If specific prices other than the imbalance settlement price are applicable to
different subsets of this total volume, it is taken care of in other calculations later in
this section.
Except as provided in paragraph A.5.3.3, the Market Operator shall calculate
the Imbalance Component Payment or Charge (CIMBuγ) for each Generator
Unit (other than an Interconnector Error Unit or an Interconnector Residual
Capacity Unit), u, in each Imbalance Settlement Period, γ, as follows:
𝐶𝐼𝑀𝐵𝑢𝛾 = 𝑃𝐼𝑀𝐵𝛾 × (𝑄𝑀𝐿𝐹𝑢𝛾 − 𝑄𝐸𝑋𝑢𝛾 )
where:
A.5.3.2
(a)
PIMBγ is the Imbalance Settlement Price in Imbalance Settlement
Period, γ[, as calculated in section on Imbalance Pricing];
(b)
QMLFuγ is the Loss-Adjusted Metered Quantity for Generator Unit, u,
in Imbalance Settlement Period, γ; and
(c)
QEXuγ is the Ex-Ante Quantity for Generator Unit, u, in Imbalance
Settlement Period, γ.
The Market Operator shall calculate the Imbalance Component Payment or
Charge (CIMBvγ) for each Supplier Unit, v, in Imbalance Settlement Period, γ,
as follows:
𝐶𝐼𝑀𝐵𝑣𝛾 = 𝑃𝐼𝑀𝐵𝛾 × (𝑄𝑀𝐿𝐹𝑣𝛾 − 𝑄𝐸𝑋𝑣𝛾 )
where:
22
(a)
PIMBγ is the Imbalance Settlement Price in Imbalance Settlement
Period, γ[, as calculated in section on Imbalance Pricing];
(b)
QMLFvγ is the Loss-Adjusted Metered Quantity for Supplier Unit, v, in
Imbalance Settlement Period, γ; and
(c)
QEXvγ is the Ex-Ante Quantity for Supplier Unit, v, in Imbalance
Settlement Period, γ.
Explanatory Note
Intention of the equation below is as follows:
A.5.3.3
-
Apply the imbalance settlement price only to instructed imbalances in the imbalance
settlement period in the case where a pumped storage unit is in pumping mode;
-
This is done to carry forward a provision from the SEM where it was decided that
uninstructed imbalances are not applicable to a pumped storage unit when in
pumping mode.
-
The QAO and QAB are the calculated instructed imbalances (difference between
dispatch level and PN’d level). The undelivered quantities corresponding to these
instructed imbalances are taken away so only the delivered portion is remunerated.
The biased quantities corresponding to these instructed imbalances are also taken
away so only the portion of this volume which is traded in the balancing market,
rather than already being traded through an ex-ante market, is remunerated. The max
of them is taken to ensure against double counting, because these volumes could be
overlapping, i.e. the same volume is both biased and undelivered;
-
There are other units who should not be remunerated for uninstructed or instructed
imbalances – one which continues on from the SEM TSC Section 5 is autonomous
generators (paragraphs 5.19 and 5.20 of SEM TSC). They are only remunerated at
the Imbalance Price through CIMB for differences against the ex-ante market
position, but are not otherwise considered in charges.
The Market Operator shall calculate the Imbalance Component Payment or
Charge (CIMBuγ) for each Pumped Storage Unit, u, in each Imbalance
Settlement Period, γ, for which it is in Pumping Mode (as determined in
paragraph A.2.1.3), as follows:
𝐶𝐼𝑀𝐵𝑢𝛾 = 𝑃𝐼𝑀𝐵𝛾 × (∑ ∑ (𝑄𝐴𝑂𝐿𝐹𝑢𝑜𝑖𝛾
𝑜
𝑖
− 𝑀𝑎𝑥(𝑄𝐴𝑂𝐵𝐼𝐴𝑆𝑢𝑜𝑖𝛾 , 𝑄𝐴𝑂𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾 ))
+ ∑ ∑ (𝑄𝐴𝐵𝐿𝐹𝑢𝑜𝑖𝛾 − 𝑀𝑖𝑛(𝑄𝐴𝐵𝐵𝐼𝐴𝑆𝑢𝑜𝑖𝛾 , 𝑄𝐴𝐵𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾 )))
𝑜
𝑖
where:
(a)
PIMBγ is the Imbalance Settlement Price in Imbalance Settlement
Period, γ[, as calculated in section on Imbalance Pricing];
(b)
QAOLFuoiγ is the Loss-Adjusted Accepted Offer Quantity for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in
Imbalance Settlement Period, γ;
(c)
QABLFuoiγ is the Loss-Adjusted Accepted Bid Quantity for Generator
Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance
Settlement Period, γ;
23
A.5.3.4
(d)
QAOUNDELuoiγ is the Undelivered Accepted Offer Quantity for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in
Imbalance Settlement Period, γ;
(e)
QABUNDELuoiγ is the Undelivered Accepted Bid Quantity for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in
Imbalance Settlement Period, γ;
(f)
QAOBIASuoiγ is the Biased Accepted Offer Quantity for Generator
Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance
Settlement Period, γ;
(g)
QABBIASuoiγ is the Biased Accepted Bid Quantity for Generator Unit,
u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement
Period, γ.
The Market Operator shall calculate the Imbalance Component Payment or
Charge (CIMBuγ) for each Interconnector Residual Capacity Unit, u, in each
Imbalance Settlement Period, γ, as follows:
𝐶𝐼𝑀𝐵𝑢𝛾 = 𝑃𝐼𝑀𝐵𝛾 × (∑ ∑(𝑄𝐴𝑂𝐿𝐹𝑢𝑜𝑖𝛾 ) + ∑ ∑(𝑄𝐴𝐵𝐿𝐹𝑢𝑜𝑖𝛾 ))
𝑜
𝑖
𝑜
𝑖
where:
(a)
PIMBγ is the Imbalance Settlement Price in Imbalance Settlement
Period, γ[, as calculated in section on Imbalance Pricing];
(b)
QAOLFuoiγ is the Loss-Adjusted Accepted Offer Quantity for
Interconnector Residual Capacity Unit, u, for Bid Offer Acceptance, o,
for Band, i, in Imbalance Settlement Period, γ; and
(c)
QABLFuoiγ is the Loss-Adjusted Accepted Bid Quantity for
Interconnector Residual Capacity Unit, u, for Bid Offer Acceptance, o,
for Band, i, in Imbalance Settlement Period, γ.
Explanatory Note
Intention of the equation below is as follows:

Apply the imbalance settlement price to the correct imbalances for each
interconnector related unit in the imbalance settlement period.

For the IRCU, only the instructed imbalances should be remunerated. Biased and
undelivered quantities are not considered here because the party behind the
IRCU, the TSO, may not be the party who caused the biased or undelivered
quantity to appear. For example, biased quantities may appear due to
interconnector technical constraints (IC Owner caused), or due to system
constraints (TSO caused), driving the Interconnector Reference Programme to be
slightly different to the Interconnector Scheduled Quantity it was intended to
represent. This is why there is no subtraction of other terms in the IRCU
calculation.

For the IEU, all imbalances other than the instructed imbalances should be
remunerated. Therefore the instructed imbalances, accepted offers and accepted
bids, are subtracted. By subtracting these terms, the imbalance charge for the IEU
considers any biased quantities and undelivered quantities among the imbalances,
as the following simplified version of the equation’s inputs shows:
o
If QAB and QAO can be simplified as (QD – QFPN). QBIAS = QEX –
QFPN, and QUNDEL = QM – QD.
o
Building QAB and QAO into the imbalance component gives:
24

A.5.3.5

CIMB = PIMB x (QM – QEX – (QAO + QAB))

= PIMB x (QM – QEX – (QD – QFPN))

= PIMB x (QM – QD – QEX + QFPN)

= PIMB x ((QM – QD) + (QEX – QFPN))

= PIMB x (QUNDEL + QBIAS)
Therefore to fully consider bias and undelivered quantities, the IEU needs to
consider these in the premium and discount component also.
The Market Operator shall calculate the Imbalance Component Payment or
Charge (CIMBuγ) for each Interconnector Error Unit, u, in each Imbalance
Settlement Period, γ, as follows:
𝐶𝐼𝑀𝐵𝑢𝛾 = 𝑃𝐼𝑀𝐵𝛾
× (𝑄𝑀𝐿𝐹𝑢𝛾 − 𝑄𝐸𝑋𝑢𝛾
− (∑ ∑(𝑄𝐴𝑂𝐿𝐹𝑢𝑜𝑖𝛾 ) + ∑ ∑(𝑄𝐴𝐵𝐿𝐹𝑢𝑜𝑖𝛾 )))
𝑜
𝑖
𝑜
𝑖
where:
A.6
(a)
PIMBγ is the Imbalance Settlement Price in Imbalance Settlement
Period, γ[, as calculated in section on Imbalance Pricing];
(b)
QMLFuγ is the Loss-Adjusted Metered Quantity for Generator Unit, u,
in Imbalance Settlement Period, γ;
(c)
QEXuγ is the Ex-Ante Quantity for Generator Unit, u, in Imbalance
Settlement Period, γ;
(d)
QAOLFuoiγ is the Loss-Adjusted Accepted Offer Quantity for
Interconnector Residual Capacity Unit, u, for Bid Offer Acceptance, o,
for Band, i, in Imbalance Settlement Period, γ; and
(e)
QABLFuoiγ is the Loss-Adjusted Accepted Bid Quantity for
Interconnector Residual Capacity Unit, u, for Bid Offer Acceptance, o,
for Band, i, in Imbalance Settlement Period, γ.
PREMIUM AND DISCOUNT COMPONENT QUANTITIES AND
PAYMENTS
Explanatory note
-
Functionality for calculating volumes of energy procured in the balancing market
for incs and decs for any desired period including allowing changes to PNs to
substitute between balancing market volumes and intraday market volumes
-
Calculating a Premium Component for Incs if the offer price for a balancing
market inc BOA is greater than the imbalance settlement price
-
Calculating a Discount Component for Decs if the bid price for a balancing market
dec BOA is less than the imbalance settlement price
-
Functionality for determining the relevant price for each BOA
25
A.6.1
Application to Imbalance Settlement Period and Imbalance Pricing
Period
A.6.1.1
The provisions in sections A.6.2 and A.6.3 are applied to two different
timeframes. For the purposes of calculating the Imbalance Price applicable
to an Imbalance Pricing Period in accordance with section [on Imbalance
Pricing], sections A.6.2 and A.6.3 are applied using the Imbalance Pricing
Period, φ, instead of the generalised period term, h. For the purposes of
calculating the settlement quantities applicable to an Imbalance Settlement
Period, sections A.6.2 and A.6.3 are applied using the Imbalance Settlement
Period, γ, instead of the generalised period term, h.
A.6.1.2
The provisions in this chapter will be based on the data available to the
Market Operator at the time of applying those provisions to the Imbalance
Pricing Period in calculating the Imbalance Price, or the time of applying
those provisions to the Imbalance Settlement Period in calculating the
settlement quantities, as applicable.
A.6.2
Calculation of Accepted Bid Quantities and Accepted Offer Quantities
Explanatory note
-
A.6.2.1
Bid Offer Acceptances (BOAs) will be calculated for deviations between the
dispatch quantity and the PN quantity.
The Market Operator shall calculate the Accepted Offer Quantities and
Accepted Bid Quantities for the purposes of the Imbalance Pricing process
and for the purposes of the Settlement process, as set out in paragraphs
A.6.2.2 to A.6.2.8, except in the case of an Interconnector Error Unit or an
Interconnector Residual Capacity Unit, where the relevant System Operator
will submit those values under paragraph A.2.5.10.
A.6.2.2
Explanatory Note
The intention of the equations in A.6.2.3 to A.6.2.6 (inclusive) is as follows:

Parts (a) and (b) calculate the function of time version (for simplicity think of this as
minute-by-minute, for all minutes within the period being considered, e.g. all minutes
within a half hour Imbalance Settlement Period) of the Bid Offer Acceptance (BOA,
subscript o), which is the amount the TSO is trading in the balancing market by
dispatching a generator. The rest of the paragraphs show how the inputs to Parts (a)
and (b) are determined for different situations. We’ll concentrate on Parts (a) and (b)
first;

This quantity needs to be split up into each generator unit, u, and each Price-Quantity
(PQ) pair quantity band, i, each BOA, o, and each period, h. This is because each
band, BOA, and period could have a different price depending on the timing of price
data submission, the timing of acceptance of BOAs, and the different prices covering
different quantity bands. So we split up the quantities in this way to ensure we can
assign the correct relevant price to each unique quantity, by calculating qBOA with
subscripts u, o, i and h;

The PQ information submitted could be entirely for a unit’s positive output range (i.e.
putting energy onto the system), for a unit’s negative output range (i.e. taking energy
from the system), or both (e.g. in the case of a pumped storage unit who can generate
or consume). Part (a) is used when considering the positive output range of the unit,
and Part (b) is used when considering the negative output range of the unit. i = 0 is
used for output quantity = 0MW, positive i means positive output (e.g. +50MW,
+70MW), negative i means negative output (unit would be consuming, e.g. -20MW, 100MW);

Parts (a) and (b) have two lines (top and bottom):
26


-
The top line is intended to follow the dispatch curve relevant for the current BOA,
o, being considered, when relevant for the band, i, being considered. At all points
in time (i.e. going along each minute within the half hour). It follows the boundary
of the previous band, until the latest dispatch curve has a value within the band.
Then it follows the dispatch curve, until it reaches the boundary of the current
band. Then it just continues out following the boundary of the current band until
the end of the period.
-
The bottom line is intended to follow the previous dispatch curve, the one relevant
before the current BOA, o. Similarly it only considers this curve when it has values
within the band in question – otherwise it follows the band boundaries.
-
The difference between the current dispatch curve, and the previous dispatch
curve, (i.e. subtracting the bottom line from the top line) is the quantity traded by
the TSO due to BOA, o. Limiting these curves to the values relevant for each
band, i, means we are splitting up this quantity into each band, so we can directly
assign a unique price, the price for that quantity band, to each quantity calculated.
Parts (a) and (b) can calculate positive quantities (incs) and negative quantities (decs)
at the same time, because it is a function of time (e.g. for the one qBOA, in minutes 17 the quantities may be positive, and then in minutes 8-29 the quantities may be
negative). The inputs to the equations are different depending on whether positive
quantities or negative quantities are being calculated. Because of this, the calculations
for qBOA need to be carried out twice: once using the inputs for positive quantities,
and again using the inputs for negative quantities. This results in two quantities for
qBOA:
-
qBOA using the conditions for incs; and
-
qBOA using the conditions for decs
These different inputs are stated in the other paragraphs:
-
For the qBOA calculation to get positive quantities, the conditions stated in the
paragraph for incs are used:
o
The first line of these conditions determines what is used on the top lines
of (a) and (b), i.e. what dispatch curve to follow. This should be the
higher of the dispatch quantity, as determined through the Instruction
Profiling Process, for the relevant BOA in question, o, or the previous
dispatch curve which was relevant prior to the current BOA. This
adjustment is made to ensure quantities are only calculated when the
dispatch quantity for order o is at a higher position than the dispatch
curve prior to order o, because when this is the case, it would result in
positive quantities.
o
The second line of these conditions determines what is used on the
bottom lines of (a) and (b), i.e. what previous dispatch curve to follow. In
this case, it is the dispatch quantity for the previous order resulting from
the instruction profiling process. This might not seem important in this
particular case, but in other equations using this formulation qDA for the
previous order could be adjusted, e.g. taking the max of the quantity
from Instruction Profiling or something else.
o
The third of these lines defines what is to be used when we are
calculating for the first order in the period, o = 1. Since we are referring
to the values for previous orders on the bottom line of part (a) and (b), (o
- 1) = 0 in this case, i.e. there is no previous order. This line sets the
default, that for the 0th case, the relevant quantity to reference is the
Final Physical Notification, FPN. This means for the first order in a
period, we are comparing the dispatch curve with the FPN curve (the
differences between FPN and dispatch are by definition balancing
market actions), and for each subsequent order in a period we reference
the previous dispatch curve rather than FPN (so we can calculate what
extra balancing market volume resulted due to the extra order).
o
The fourth and fifth of these lines similarly define what is the 0 th case,
this time for the PQ bands we are using to split up the volumes. We want
to calculate for all bands submitted by a unit, i.e. i = 1, 2, 3, or i = -1, -2, 3, but we refer to the previous band value also, (i – 1) or (i + 1), so that
we can calculate only values within the current band’s range (between
the previous band’s upper range and current band’s upper range). This
27
is to ensure that when we are calculating values in the bands i = 1 or i = 1, when we refer to the previous one ((i – 1) when discussing i = 1, or (i +
1) when discussing i = -1) that the range value we are taking for i = 0 is
0MW. This is to have a clean split between positive output ranges (i > 0)
and negative output ranges (i < 0) when both exist, or when only one
exists, providing the 0th case to ensure the algebra works when
calculating for the first band.
-

A.6.2.3
For the qBOA calculation to get negative quantities, the conditions stated in the
paragraph for decs are used:
o
The first line of these conditions is similar to the first line in the conditions
for incs explained above, finding the dispatch curve to follow. In this case
we take the minimum of the previous curve or the dispatch quantity from
instruction profiling, because negative values will only be calculated if the
dispatch quantity is lower than the previous curve;
o
The second line is for the same reasons as incs;
o
The third of these lines similarly defines what is to be used for first BOA
where there is no previous dispatch curve for an order to reference. In
this case, instead of only referencing the FPN like for positive quantities
under the paragraph for incs, is takes the minimum of the FPN curve and
the Outturn Availability curve. This is to make sure cases where an
action taken in the balancing market due to a reduction in availability is
not seen as accepting a bid, but is rather an imbalance. For example, if a
unit trips, their FPN would remain unchanged, their availability would
drop to 0, and the TSO would dispatch the unit down to 0 to match their
availability (resulting in a dispatch quantity, qD). If availability wasn’t
included in this line, this action would be calculated as the TSO
accepting a Bid from the unit who tripped, but this is not correct: it should
only appear as an imbalance, without any quantity calculated. Therefore
we take the min of the availability quantity and the FPN quantity: if the
action is due to a change in availability, no quantity should be calculated,
so the top line in Part (a) or (b) would be a dispatch curve, and the
bottom line of part (a) or (b) would reference the availability curve, both
of these should be equal, meaning no quantity calculated.
The fourth and fifth lines are for the same reasons as the paragraphs for incs.
The Market Operator shall calculate two values for the Accepted Bid Offer
Quantity (qBOAuoih(t)) as a function of time, for each Generator Unit, u, for
each Bid Offer Acceptance, o, for each Band, i, in period, h, calculating
separately one value for all Incs resulting from the Bid Offer Acceptance and
one value for all Decs resulting from the Bid Offer Acceptance, as follows:
(a)
For i > 0
𝑞𝐵𝑂𝐴𝑢𝑜𝑖ℎ (𝑡) = 𝑀𝑎𝑥{𝑀𝑖𝑛{𝑞𝐷𝐴𝑢𝑜ℎ (𝑡), 𝑞𝐵𝑂𝑈𝑅𝑢𝑖ℎ (𝑡)}, 𝑞𝐵𝑂𝑈𝑅𝑢(𝑖−1)ℎ (𝑡)}
− 𝑀𝑎𝑥{𝑀𝑖𝑛{𝑞𝐷𝐴𝑢(𝑜−1)ℎ (𝑡), 𝑞𝐵𝑂𝑈𝑅𝑢𝑖ℎ (𝑡)}, 𝑞𝐵𝑂𝑈𝑅𝑢(𝑖−1)ℎ (𝑡)}
(b)
For i < 0:
𝑞𝐵𝑂𝐴𝑢𝑜𝑖ℎ (𝑡) = 𝑀𝑖𝑛{𝑀𝑎𝑥{𝑞𝐷𝐴𝑢𝑜ℎ (𝑡), 𝑞𝐵𝑂𝐿𝑅𝑢𝑖ℎ (𝑡)}, 𝑞𝐵𝑂𝐿𝑅𝑢(𝑖+1)ℎ (𝑡)}
− 𝑀𝑖𝑛{𝑀𝑎𝑥{𝑞𝐷𝐴𝑢(𝑜−1)ℎ (𝑡), 𝑞𝐵𝑂𝐿𝑅𝑢𝑖ℎ (𝑡)}, 𝑞𝐵𝑂𝐿𝑅𝑢(𝑖+1)ℎ (𝑡)}
A.6.2.4
When calculating the value for the Accepted Bid Offer Quantity (qBOAuoih(t))
for the Incs resulting from the Bid Offer Acceptance, the Market Operator
shall calculate the relevant variables as follows:
28
𝑞𝐷𝐴𝑢𝑜ℎ (𝑡) = 𝑀𝑎𝑥 (𝑞𝐷𝑢𝑜ℎ (𝑡), 𝑞𝐷𝐴𝑢(𝑜−1)ℎ (𝑡))
𝑞𝐷𝐴𝑢(𝑜−1)ℎ (𝑡) = 𝑞𝐷𝑢(𝑜−1)ℎ (𝑡)
𝑞𝐷𝑢(𝑜=0)ℎ (𝑡) = 𝑞𝐹𝑃𝑁𝑢ℎ (𝑡)
𝑞𝐵𝑂𝑈𝑅𝑢(𝑖=0)ℎ (𝑡) = 0
𝑞𝐵𝑂𝐿𝑅𝑢(𝑖=0)ℎ (𝑡) = 0
A.6.2.5
When calculating the value for the Accepted Bid Offer Quantity (qBOAuoih(t))
for the Decs resulting from the Bid Offer Acceptance, the Market Operator
shall calculate the relevant variables as follows:
𝑞𝐷𝐴𝑢𝑜ℎ (𝑡) = 𝑀𝑖𝑛 (𝑞𝐷𝑢𝑜ℎ (𝑡), 𝑞𝐷𝐴𝑢(𝑜−1)ℎ (𝑡))
𝑞𝐷𝐴𝑢(𝑜−1)ℎ (𝑡) = 𝑞𝐷𝑢(𝑜−1)ℎ (𝑡)
𝑞𝐷𝑢(𝑜=0)ℎ (𝑡) = 𝑀𝑖𝑛(𝑞𝐹𝑃𝑁𝑢ℎ (𝑡), 𝑞𝐴𝑉𝐴𝐼𝐿𝑂𝑢ℎ (𝑡))
𝑞𝐵𝑂𝑈𝑅𝑢(𝑖=0)ℎ (𝑡) = 0
𝑞𝐵𝑂𝐿𝑅𝑢(𝑖=0)ℎ (𝑡) = 0
A.6.2.6
For the purposes of paragraphs A.6.2.3 to A.6.2.5:
(a)
qDuoh(t) is the Dispatch Quantity as a function of time for Generator
Unit, u, for Bid Offer Acceptance, o, in period, h;
(b)
qDAuoh(t) is the Adjusted Dispatch Quantity as a function of time for
Generator Unit, u, for Bid Offer Acceptance, o, in period, h;
(c)
qBOURuih(t) is the Bid Offer Upper Range Quantity as a function of
time for Generator Unit, u, for Band, i, in period, h;
(d)
qBOLRuih(t) is the Bid Offer Lower Range Quantity as a function of
time for Generator Unit, u, for Band, i, in period, h;
(e)
qFPNuh(t) is the Final Physical Notification Quantity as a function of
time for Generator Unit, u, in period, h;
(f)
qAVAILOuh(t) is the Outturn Availability Quantity as a function of time
for Generator Unit, u, in period, h;
(g)
(o – 1) is for the previous Bid Offer Acceptance in respect of the same
period, h.
(h)
(i – 1) is for the previous Band when considering Bands in the positive
direction (i > 0);
(i)
(i + 1) is for the previous Band when considering Bands in the
negative direction (i < 0);
(j)
(o = 0) or (i = 0) is for the 0th value for the relevant aspect (i.e. the
implicit default value before an explicit Bid Offer Acceptance, o; the
value for Band, i, where i = 0).
29
Explanatory Note
The intention of the equations below is as follows:
In the previous step, qBOA was calculated containing both positive and negative values in
different minutes. It was also calculated twice: one time each with the inputs for incs and inputs
for decs. These equations split out the negatives and the positives (positives from max of the
value in each minute and zero, negatives from min of the value and zero), from the relevant
calculation (for positive values, we care about the inputs for incs, for negative values, we care
about the inputs for decs).
A.6.2.7
The Market Operator shall calculate the Accepted Offer Quantity (qAOuoih(t))
as a function of time, and the Accepted Bid Quantity (qABuoih(t)) as a function
of time, for each Generator Unit, u, for each Bid Offer Acceptance, o, for
each Band, i, in period, h, separately for the Incs and Decs, as follows:
𝑞𝐴𝑂𝑢𝑜𝑖ℎ (𝑡) = 𝑀𝑎𝑥(𝑞𝐵𝑂𝐴𝑢𝑜𝑖ℎ (𝑡) 𝑓𝑜𝑟 𝐼𝑛𝑐𝑠, 0)
𝑞𝐴𝐵𝑢𝑜𝑖ℎ (𝑡) = 𝑀𝑖𝑛(𝑞𝐵𝑂𝐴𝑢𝑜𝑖ℎ (𝑡) 𝑓𝑜𝑟 𝐷𝑒𝑐𝑠, 0)
where:
(a)
qBOAuoih(t) is the Accepted Bid Offer Quantity as a function of time for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in period,
h.
Explanatory Note
The intention of the paragraph below is as follows:
-
Because everything so far has been done as a function of time granularity (minute-byminute), but settlement and pricing are done at a period granularity (5 minutes, 30 minutes),
the function of time results need to be converted into period results by integrating the values
of the function of time curves over the period in question.
A.6.2.8
The Market Operator shall calculate the Accepted Offer Quantity (QAOuoih)
and the Accepted Bid Quantity (QABuoih) for Generator Unit u, in period h, by
integrating the associated function of time Accepted Offer Quantity
(qAOuoih(t)) and Accepted Bid Quantity (qABuoih(t)) with respect to time across
the period, h.
A.6.3
Determination of Accepted Bid and Accepted Offer Prices
A.6.3.1
Except in the case of an Interconnector Error Unit or an Interconnector
Residual Capacity Unit, the Bid Offer Price (PBOuβoih) for each Accepted Bid
Quantity and each Accepted Offer Quantity shall be:
A.6.3.2
(a)
For each Accepted Offer Quantity, QAOuoih, the incremental price in
the Band, i, provided in the relevant Commercial Offer Data set as
determined in section A.3.2;
(b)
For each Accepted Bid Quantity, QABuoih, the decremental price in the
Band, i, provided in the relevant Commercial Offer Data set as
determined in section A.3.2.
The Bid Offer Price (PBOuβoih) for each individual Accepted Bid Quantity and
Accepted Offer Quantity, for each Bid Offer Acceptance, o, relevant to an
Interconnector Residual Capacity Unit, u, shall be the values submitted by
the System Operator for the relevant Interconnector, l, in accordance with
paragraph A.2.5.10.
30
A.6.4
Calculation of Trade in the Opposite Direction to the TSO Quantities
Explanatory notes
-
If a change in PN constitutes a trade in the opposite direction to the TSO – The volume to
which the premium/discount is attributed should not include the volume which arises from
this change;
-
Calculate the volume arising through PN changes which result in an increase to the volume
of a balancing market order (“Trade in the Opposite Direction to the TSO”)
-
Remove the volume from Trade in the Opposite Direction to the TSO from the premium or
discount component
Explanatory Note
The intention of the equations in these equations is as follows:
-
The format of these equations is similar to qBOA. This is intentional: both of these
calculate volumes in the same manner. qBOAWTOTSO has a few tweaks which makes
it different:
o
At its simplest, TOTSO is where the FPN is in a position versus the PN at the
time of accepting the order such that it increases the volume of the order. E.g.
if an inc order was accepted of 100MWh with PN1, but then the value when
calculated with the FPN was 150MWh, it means the FPN was decreased
versus PN1 to increase the volume of the order by 50MWh.
o
Parts (a) and (b) are the same as for qBOAs, subtracting the current dispatch
quantity (top line) from the previous dispatch quantity (bottom line), while
splitting up by band, period, and BOA;
o
In the conditions for incs and decs, a tweak is made where instead of the
second line being qDA(o-1) = qD(o-1), there are new rules around which
values we want to use in the previous dispatch quantity in order to exclude all
values which are due to trade opposite TSO.
o
The third line outlines some of these new rules through qDAWTOTSO(o-1).
The intention is to follow the previous dispatch quantity, qD(o-1), calculating
qBOAs like normal, unless it crosses the quantity of the PN which was present
at the time (beta) of accepting order (o-1) (qD(o-1) crossing to below this
PNbeta(o-1) for incs, and qD(o-1) crossing to above this PNbeta(o-1) for
decs). When this crossing occurs, we need to reference the 0 th case, qD(0), to
see what quantity to follow. We care about this “crossing” point because it
determines if the relationship between the PN at the time of the order
acceptance and the FPN, and isolates where TOTSO might be occurring for
one order but not for another in the same period (e.g. order (o-1) might have
TOTSO applied, but order o might not – might need to refer to FPN quantity
for order o like a normal qBOA, while referring to the PNbeta(o-1) quantity for
order (o-1)).
o
The fourth and fifth lines of these equations set out the different rules for the
0th case for excluding TOTSO volumes, determining whether for the previous
dispatch quantity to use in parts (a) and (b) we should:
o

Follow the PNbeta(o) quantity to make sure we exclude TOTSO
volumes, if the PNbeta(o) quantity is different to the FPN quantity or;

Follow the FPN quantity like a normal qBOA, because the
relationship between the PN at the time of acceptance and the FPN
is such that there is no volume due to TOTSO.

We only care about this tweak when the current dispatch quantity,
qDAo, is greater than qPNbeta(o) for incs, or less than qPNbeta(o)
for decs, because when the opposite of these cases occur, it is not
considered volume due to TOTSO, it is considered volume where an
initial inc was switched to a dec, or vice versa, which is not intended
to be excluded as part of this formulation.
The 6th and 7th lines of the conditions for incs and decs are the same as for
31
qBOA
Without Trade Opposite TSO
These equations calculate the volume of the accepted bid/offer quantity that is left after volumes
due to trades entered into in the opposite direction to the TSO’s dispatch instruction (this is what
is meant by quantity “without trade opposite TSO”).
A.6.4.1
Where the Regulatory Authorities have given notice to the Market Operator
of a requirement to include QAOTOTSOuoiγ and QABTOTSOuoiγ in the
calculation of Premium and Discount Component Payments, the Market
Operator shall, from the time the notice takes effect, calculate
QAOTOTSOuoiγ and QABTOTSOuoiγ in accordance with the procedure set out
in paragraphs A.6.4.5 to A.6.4.11.
A.6.4.2
Where the Regulatory Authorities have not given a notice under paragraph
A.6.4.1, or have withdrawn a notice under that paragraph, the Market
Operator shall set the values of QAOTOTSOuoiγ and QABTOTSOuoiγ to zero.
A.6.4.3
A notice under paragraph A.6.4.1, or a withdrawal under that paragraph,
takes effect on the later of:
(a)
The time specified in the notice or withdrawal; and
(b)
The expiration of [two months] after the notice was received by the
Market Operator.
A.6.4.4
If the Regulatory Authorities give a notice under paragraph A.6.4.1 or
withdrawal under that paragraph, the [Market Operator] shall promptly
publish it.
A.6.4.5
The Market Operator shall calculate two values for the Without Trade
Opposite TSO Accepted Bid Offer Quantity (qBOAWTOTSOuoiγ(t)) as a
function of time, for each Generator Unit, u, for each Bid Offer Acceptance,
o, for each Band, i, in period, h, calculating separately one value for all Incs
resulting from the Bid Offer Acceptance and one value for all Decs resulting
from the Bid Offer Acceptance, as follows:
(a)
For i > 0:
𝑞𝐵𝑂𝐴𝑊𝑇𝑂𝑇𝑆𝑂𝑢𝑜𝑖𝛾 (𝑡)
= 𝑀𝑎𝑥{𝑀𝑖𝑛{𝑞𝐷𝐴𝑢𝑜𝛾 (𝑡), 𝑞𝐵𝑂𝑈𝑅𝑢𝑖𝛾 (𝑡)}, 𝑞𝐵𝑂𝑈𝑅𝑢(𝑖−1)𝛾 (𝑡)}
− 𝑀𝑎𝑥{𝑀𝑖𝑛{𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡), 𝑞𝐵𝑂𝑈𝑅𝑢𝑖𝛾 (𝑡)}, 𝑞𝐵𝑂𝑈𝑅𝑢(𝑖−1)𝛾 (𝑡)}
(b)
For i < 0:
𝑞𝐵𝑂𝐴𝑊𝑇𝑂𝑇𝑆𝑂𝑢𝑜𝑖𝛾 (𝑡)
= 𝑀𝑖𝑛{𝑀𝑎𝑥{𝑞𝐷𝐴𝑢𝑜𝛾 (𝑡), 𝑞𝐵𝑂𝐿𝑅𝑢𝑖𝛾 (𝑡)}, 𝑞𝐵𝑂𝐿𝑅𝑢(𝑖+1)𝛾 (𝑡)}
− 𝑀𝑖𝑛{𝑀𝑎𝑥{𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡), 𝑞𝐵𝑂𝐿𝑅𝑢𝑖𝛾 (𝑡)}, 𝑞𝐵𝑂𝐿𝑅𝑢(𝑖+1)𝛾 (𝑡)}
A.6.4.6
When calculating the value for the Without Trade Opposite TSO Accepted
Bid Offer Quantity (qBOAWTOTSOuoiγ(t)) for the Incs resulting from the Bid
Offer Acceptance, the Market Operator shall calculate the relevant variables
as follows:
𝑞𝐷𝐴𝑢𝑜𝛾 (𝑡) = 𝑀𝑎𝑥 (𝑞𝐷𝑢𝑜𝛾 (𝑡), 𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡))
32
𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡) = 𝑞𝐷𝐴𝑊𝑇𝑂𝑇𝑆𝑂𝑢(𝑜−1)𝛾 (𝑡)
𝐼𝑓 𝑞𝐷𝑢(𝑜−1)𝛾 (𝑡) ≥ 𝑞𝑃𝑁𝑢𝛽(𝑜−1)𝛾 (𝑡), 𝑡ℎ𝑒𝑛
𝑞𝐷𝐴𝑊𝑇𝑂𝑇𝑆𝑂𝑢(𝑜−1)𝛾 (𝑡) = 𝑞𝐷𝑢(𝑜−1)𝛾 (𝑡)
𝑒𝑙𝑠𝑒
𝑞𝐷𝐴𝑊𝑇𝑂𝑇𝑆𝑂𝑢(𝑜−1)𝛾 (𝑡) = 𝑞𝐷𝑢(𝑜=0)𝛾 (𝑡)
𝑞𝐷𝑢(𝑜=0)𝛾 (𝑡) = 𝑞𝐷𝑊𝑇𝑂𝑇𝑆𝑂𝑢(𝑜=0)𝛾 (𝑡)
𝐼𝑓 𝑞𝐷𝑢𝑜𝛾 (𝑡) ≥ 𝑞𝑃𝑁𝑢𝛽𝑜𝛾 (𝑡), 𝑡ℎ𝑒𝑛
𝑞𝐷𝑊𝑇𝑂𝑇𝑆𝑂𝑢(𝑜=0)𝛾 (𝑡) = 𝑀𝑎𝑥 (𝑞𝑃𝑁𝑢𝛽𝑜𝛾 (𝑡), 𝑞𝐹𝑃𝑁𝑢𝛾 (𝑡))
𝑒𝑙𝑠𝑒
𝑞𝐷𝑊𝑇𝑂𝑇𝑆𝑂𝑢(𝑜=0)𝛾 (𝑡) = 𝑞𝐹𝑃𝑁𝑢𝛾 (𝑡)
𝑞𝑃𝑁𝑢𝛽(𝑜=0)𝛾 (𝑡) = 0
𝑞𝐵𝑂𝑈𝑅𝑢(𝑖=0)𝛾 (𝑡) = 0
𝑞𝐵𝑂𝐿𝑅𝑢(𝑖=0)𝛾 (𝑡) = 0
A.6.4.7
When calculating the value for the Without Trade Opposite TSO Accepted
Bid Offer Quantity (qBOAWTOTSOuoiγ(t)) for the Decs resulting from the Bid
Offer Acceptance, the Market Operator shall calculate the relevant variables
as follows:
𝑞𝐷𝐴𝑢𝑜𝛾 (𝑡) = 𝑀𝑖𝑛 (𝑞𝐷𝑢𝑜𝛾 (𝑡), 𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡))
𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡) = 𝑞𝐷𝐴𝑊𝑇𝑂𝑇𝑆𝑂𝑢(𝑜−1)𝛾 (𝑡)
𝐼𝑓 𝑞𝐷𝑢(𝑜−1)𝛾 (𝑡) ≤ 𝑞𝑃𝑁𝑢𝛽(𝑜−1)𝛾 (𝑡), 𝑡ℎ𝑒𝑛
𝑞𝐷𝐴𝑊𝑇𝑂𝑇𝑆𝑂𝑢(𝑜−1)𝛾 (𝑡) = 𝑞𝐷𝑢(𝑜−1)𝛾 (𝑡)
𝑒𝑙𝑠𝑒
𝑞𝐷𝐴𝑊𝑇𝑂𝑇𝑆𝑂𝑢(𝑜−1)𝛾 (𝑡) = 𝑞𝐷𝑢(𝑜=0)𝛾 (𝑡)
𝑞𝐷𝑢(𝑜=0)𝛾 (𝑡) = 𝑞𝐷𝑊𝑇𝑂𝑇𝑆𝑂𝑢(𝑜=0)𝛾 (𝑡)
𝐼𝑓 𝑞𝐷𝑢𝑜𝛾 (𝑡) ≤ 𝑞𝑃𝑁𝑢𝛽𝑜𝛾 (𝑡), 𝑡ℎ𝑒𝑛
𝑞𝐷𝑊𝑇𝑂𝑇𝑆𝑂𝑢(𝑜=0)𝛾 (𝑡) = 𝑀𝑖𝑛 (𝑞𝑃𝑁𝑢𝛽𝑜𝛾 (𝑡), 𝑞𝐹𝑃𝑁𝑢𝛾 (𝑡), 𝑞𝐴𝑉𝐴𝐼𝐿𝑂𝑢𝛾 (𝑡))
𝑒𝑙𝑠𝑒
𝑞𝐷𝑊𝑇𝑂𝑇𝑆𝑂𝑢(𝑜=0)𝛾 (𝑡) = 𝑀𝑖𝑛 (𝑞𝐹𝑃𝑁𝑢𝛾 (𝑡), 𝑞𝐴𝑉𝐴𝐼𝐿𝑂𝑢𝛾 (𝑡))
𝑞𝑃𝑁𝑢𝛽(𝑜=0)𝛾 (𝑡) = 0
𝑞𝐵𝑂𝑈𝑅𝑢(𝑖=0)𝛾 (𝑡) = 0
𝑞𝐵𝑂𝐿𝑅𝑢(𝑖=0)𝛾 (𝑡) = 0
A.6.4.8
For the purposes of paragraphs A.6.4.5 to A.6.4.7:
33
A.6.4.9
(a)
qDuoγ(t) is the Dispatch Quantity as a function of time for Generator
Unit, u, for Bid Offer Acceptance, o, in Imbalance Settlement Period,
γ;
(b)
qDAuoγ(t) is the Adjusted Dispatch Quantity as a function of time for
Generator Unit, u, for Bid Offer Acceptance, o, in Imbalance
Settlement Period, γ;
(c)
qDWTOTSOuoγ(t) is the Without Trade Opposite TSO Dispatch
Quantity as a function of time for Generator Unit, u, for Bid Offer
Acceptance, o, in Imbalance Settlement Period, γ;
(d)
qDAWTOTSOuoγ(t) is the Without Trade Opposite TSO Adjusted
Dispatch Quantity as a function of time for Generator Unit, u, for Bid
Offer Acceptance, o, in Imbalance Settlement Period, γ;
(e)
qBOURuiγ(t) is the Bid Offer Upper Range Quantity as a function of
time for Generator Unit, u, for Band, i, in Imbalance Settlement
Period, γ;
(f)
qBOLRuiγ(t) is the Bid Offer Lower Range Quantity as a function of
time for Generator Unit, u, for Band, i, in Imbalance Settlement
Period, γ;
(g)
qFPNuγ(t) is the Final Physical Notification Quantity as a function of
time for Generator Unit, u, in Imbalance Settlement Period, γ;
(h)
qPNuβoγ(t) is the Physical Notification Quantity as a function of time for
Generator Unit, u, time stamped, β, as the last one submitted by the
relevant Participant before Bid Offer Acceptance, o, in Imbalance
Settlement Period, γ;
(i)
qAVAILOuγ(t) is the Outturn Availability Quantity as a function of time
for Generator Unit, u, in Imbalance Settlement Period, γ;
(j)
(o – 1) is for the previous Bid Offer Acceptance for the unit;
(k)
(i – 1) is for the previous Band when considering Bands in the positive
direction (i > 0);
(l)
(i + 1) is for the previous Band when considering Bands in the
negative direction (i < 0);
(m)
(o = 0) or (i = 0) is for the 0th value for the relevant aspect (i.e. the
implicit default value before an explicit Bid Offer Acceptance, o; the
value for Band, i, where i = 0).
The Market Operator shall calculate the Without Trade Opposite TSO
Accepted Offer Quantity (qAOWTOTSOuoiγ(t)) as a function of time, and the
Without Trade Opposite TSO Accepted Bid Quantity (qABWTOTSOuoiγ(t)) as
a function of time, for each Generator Unit, u, for each Bid Offer Acceptance,
o, for each Band, i, in Imbalance Settlement Period, γ, as follows:
𝑞𝐴𝑂𝑊𝑇𝑂𝑇𝑆𝑂𝑢𝑜𝑖𝛾 (𝑡) = 𝑀𝑎𝑥(𝑞𝐵𝑂𝐴𝑊𝑇𝑂𝑇𝑆𝑂𝑢𝑜𝑖𝛾 (𝑡) 𝑓𝑜𝑟 𝐼𝑛𝑐𝑠, 0)
𝑞𝐴𝐵𝑊𝑇𝑂𝑇𝑆𝑂𝑢𝑜𝑖𝛾 (𝑡) = 𝑀𝑖𝑛(𝑞𝐵𝑂𝐴𝑊𝑇𝑂𝑇𝑆𝑂𝑢𝑜𝑖𝛾 (𝑡) 𝑓𝑜𝑟 𝐷𝑒𝑐𝑠, 0)
where:
34
(a)
qBOAWTOTSOuoiγ(t) is the Without Trade Opposite TSO Accepted
Bid Offer Quantity as a function of time for Generator Unit, u, for Bid
Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ.
Explanatory Note
The intention of the equations below is as follows:
-
The previous calculations work out a volume which is qBOA but excluding volumes due
to TOTSO. To find the volumes due to TOTSO, this can be subtracted from the actual
qBOA.
A.6.4.10 The Market Operator shall calculate the Trade Opposite TSO Accepted Offer
Quantity (qAOTOTSOuoiγ(t)) as a function of time, and the Trade Opposite
TSO Accepted Bid Quantity (qABTOTSOuoiγ(t)) as a function of time, for each
Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in
Imbalance Settlement Period, γ, as follows:
𝑞𝐴𝑂𝑇𝑂𝑇𝑆𝑂𝑢𝑜𝑖𝛾 (𝑡) = 𝑀𝑎𝑥(𝑞𝐴𝑂𝑢𝑜𝑖𝛾 (𝑡) − 𝑞𝐴𝑂𝑊𝑇𝑂𝑇𝑆𝑂𝑢𝑜𝑖𝛾 (𝑡), 0)
𝑞𝐴𝐵𝑇𝑂𝑇𝑆𝑂𝑢𝑜𝑖𝛾 (𝑡) = 𝑀𝑖𝑛(𝑞𝐴𝐵𝑢𝑜𝑖𝛾 (𝑡) − 𝑞𝐴𝐵𝑊𝑇𝑂𝑇𝑆𝑂𝑢𝑜𝑖𝛾 (𝑡), 0)
where:
(a)
qAOuoiγ(t) is the Accepted Offer Quantity as a function of time for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in
Imbalance Settlement Period, γ;
(b)
qABuoiγ(t) is the Accepted Bid Quantity as a function of time for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in
Imbalance Settlement Period, γ;
(c)
qAOWTOTSOuoiγ(t) is the Without Trade Opposite TSO Accepted
Offer Quantity as a function of time for Generator Unit, u, for Bid Offer
Acceptance, o, for Band, i, in Imbalance Settlement Period, γ; and
(d)
qABWTOTSOuoiγ(t) is the Without Trade Opposite TSO Accepted Bid
Quantity as a function of time for Generator Unit, u, for Bid Offer
Acceptance, o, for Band, i, in Imbalance Settlement Period, γ.
A.6.4.11 The Market Operator shall calculate the Trade Opposite TSO Accepted Offer
Quantity (QAOTOTSOuoiγ), and the Trade Opposite TSO Accepted Bid
Quantity (QABTOTSOuoiγ), for Generator Unit u, for the Imbalance Settlement
Period, γ, by integrating the associated function of time quantities Trade
Opposite TSO Accepted Offer Quantity (qAOTOTSOuoiγ(t)) and Trade
Opposite TSO Accepted Bid Quantity (qABTOTSOuoiγ(t)) with respect to time
across the Imbalance Settlement Period, γ.
A.6.4.12 The provisions of section A.6.4 do not apply to an Interconnector Error Unit.
A.6.5
Calculation of Non-Firm Decremental Quantities
Explanatory notes:
-
If a dec bid was accepted from a participant within their non-firm capacity range – the
volume to which the premium/discount is attributed should not include this component
of the volume;
-
Functionality for determining the situations when the calculations for non-firm
constraints are needed.
-
Calculate the volume if a dec balancing market action occurring over the non-firm
35
output range of a unit when the situation requires this calculation.
-
A.6.5.1
Remove this non-firm volume from the discount component.
The Market Operator shall determine the Firm Access Quantity (qFAQuγ(t))
as a function of time for each Generator Unit, u, in Trading Site, s, with NonFirm Access in Imbalance Settlement Period, γ, as follows:
Note: intention of the equations are as follows:
-
Similar to a current provision in the TSC, because firm access is assigned to
trading sites rather than units, in cases where there is non-firm access on a
trading site there needs to be some rationale to split how much firmness each unit
on the site has. This rationale is based on how much decremental bids have been
accepted on the unit, because firmness only affects the settlement of these orders
The first line works out how much non-firmness there is on the site, i.e. how much
in net does generation and demand on the site intend to be on the system above
its firm access quantity. Because metered demand (QMvgamma) can only be at
an integrated settlement period granularity, this equation is carried out to that
granularity.
The next line assigns this non-firmness to units pro-rata based on how much of
the overall site decremental orders they received, so that the unit with the most
dec orders gets most of the non-firmness. It assumes that a unit is initially firm up
to its FPN, and then decreases this firmness by the allotted amount of nonfirmness. Because the intended result is a function-of-time MW result, while the
equations are being carried out on an integrated period MWh level, it needs to be
divided by the period (in hours) in question, the imbalance settlement period (0.5
hours) to get the MW result.]
-
-
𝑄𝐹𝑃𝑁𝑁𝐹𝑠𝛾 = 𝑀𝑎𝑥 ( ∑
𝑄𝐹𝑃𝑁𝑢𝛾 +
𝑎𝑙𝑙 𝑢 𝑖𝑛 𝑠
𝐼𝑓
∑
∑
𝑄𝑀𝑣𝛾 − 𝑄𝐹𝐴𝑄𝑠𝛾 , 0)
𝑎𝑙𝑙 𝑣 𝑖𝑛 𝑠
∑ ∑ 𝑄𝐴𝐵𝑢𝑜𝑖𝛾 < 0, 𝑡ℎ𝑒𝑛
𝑎𝑙𝑙 𝑢 𝑖𝑛 𝑠 𝑜
𝑖
∑𝑜 ∑𝑖 𝑄𝐴𝐵𝑢𝑜𝑖𝛾
𝑀𝑎𝑥 (𝑄𝐹𝑃𝑁𝑢𝛾 − 𝑄𝐹𝑃𝑁𝑁𝐹𝑠𝛾 (
) , 0)
∑𝑎𝑙𝑙 𝑢 𝑖𝑛 𝑠 ∑𝑜 ∑𝑖 𝑄𝐴𝐵𝑢𝑜𝑖𝛾
𝑞𝐹𝐴𝑄𝑢𝛾 (𝑡) =
𝐷𝐼𝑆𝑃
𝐸𝑙𝑠𝑒
𝑄𝐹𝑃𝑁𝑢𝛾
𝑞𝐹𝐴𝑄𝑢𝛾 (𝑡) =
𝐷𝐼𝑆𝑃
where:
(a)
QFPNNFsγ is the Non-Firm Final Physical Notification Quantity for
Trading Site, s, in Imbalance Settlement Period, γ;
(b)
QFPNuγ is the Final Physical Notification Quantity for Generator Unit,
u, in Imbalance Settlement Period, γ;
(c)
QMvγ is the Metered Quantity for Supplier Unit, v, in Imbalance
Settlement Period, γ;
(d)
QFAQsγ is the Firm Access Quantity for Trading Site, s, in Imbalance
Settlement Period, γ;
(e)
QABuoiγ is the Accepted Bid Quantity for Generator Unit, u, for Bid
Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;
(f)
∑𝑎𝑙𝑙 𝑣 𝑖𝑛 𝑠 means the value for the single Supplier Unit, v, in Trading
Site, s, in accordance with [paragraph in registration stating that
Trading Sites may only have a single Supplier Unit]; and
36
(g)
A.6.5.2
DISP is the Imbalance Settlement Period Duration.
The Market Operator shall calculate the value of the Non-Firm Accepted Bid
Offer Quantity (qBOANFuoiγ(t)) as a function of time, for each Generator Unit,
u, for all Decs resulting from each Bid Offer Acceptance, o, for each Band, i,
in Imbalance Settlement Period, γ, as follows:
Note: the intention of these equations are as follows:
-
-
(a)
A similar formulation to a normal qBOA calculation but with tweaks to calculate only
those dec volumes which are non-firm. Parts (a) and (b) of this equation are the same
as for qBOA and only the inputs for decs are needed;
The tweaks come the conditions for decs, where in order to calculate those volumes
which were non-firm (i.e. all dec volumes for where the FPN quantity is higher than
the firmness quantity calculated in the previous section), the second line (for qDANF)
is adjusted to take the maximum of the current dispatch quantity and the firm access
quantity. This means that it will only calculate those parts of the dec bid accepted
which were above the FAQ, following the FAQ quantity when the dispatch quantity
goes below it. All other lines are the same as for qBOA.
For i > 0:
𝑞𝐵𝑂𝐴𝑁𝐹𝑢𝑜𝑖𝛾 (𝑡)
= 𝑀𝑎𝑥{𝑀𝑖𝑛{𝑞𝐷𝐴𝑢𝑜𝛾 (𝑡), 𝑞𝐵𝑂𝑈𝑅𝑢𝑖𝛾 (𝑡)}, 𝑞𝐵𝑂𝑈𝑅𝑢(𝑖−1)𝛾 (𝑡)}
− 𝑀𝑎𝑥{𝑀𝑖𝑛{𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡), 𝑞𝐵𝑂𝑈𝑅𝑢𝑖𝛾 (𝑡)}, 𝑞𝐵𝑂𝑈𝑅𝑢(𝑖−1)𝛾 (𝑡)}
(b)
For i < 0:
𝑞𝐵𝑂𝐴𝑁𝐹𝑢𝑜𝑖𝛾 (𝑡)
= 𝑀𝑖𝑛{𝑀𝑎𝑥{𝑞𝐷𝐴𝑢𝑜𝛾 (𝑡), 𝑞𝐵𝑂𝐿𝑅𝑢𝑖𝛾 (𝑡)}, 𝑞𝐵𝑂𝐿𝑅𝑢(𝑖+1)𝛾 (𝑡)}
− 𝑀𝑖𝑛{𝑀𝑎𝑥{𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡), 𝑞𝐵𝑂𝐿𝑅𝑢𝑖𝛾 (𝑡)}, 𝑞𝐵𝑂𝐿𝑅𝑢(𝑖+1)𝛾 (𝑡)}
A.6.5.3
When calculating the value for the qBOANFuoiγ(t), the Market Operator shall
calculate the relevant variables as follows:
𝑞𝐷𝐴𝑢𝑜𝛾 (𝑡) = 𝑞𝐷𝐴𝑁𝐹𝑢𝑜𝛾 (𝑡)
𝑞𝐷𝐴𝑁𝐹𝑢𝑜𝛾 (𝑡) = 𝑀𝑖𝑛 (𝑀𝑎𝑥 (𝑞𝐷𝑢𝑜𝛾 (𝑡), 𝑞𝐹𝐴𝑄𝑢𝛾 (𝑡)) , 𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡))
𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡) = 𝑞𝐷𝑢(𝑜−1)𝛾 (𝑡)
𝑞𝐷𝑢(𝑜=0)𝛾 (𝑡) = 𝑀𝑖𝑛 (𝑞𝐹𝑃𝑁𝑢𝛾 (𝑡), 𝑞𝐴𝑉𝐴𝐼𝐿𝑂𝑢𝛾 (𝑡))
𝑞𝐵𝑂𝑈𝑅𝑢(𝑖=0)𝛾 (𝑡) = 0
𝑞𝐵𝑂𝐿𝑅𝑢(𝑖=0)𝛾 (𝑡) = 0
A.6.5.4
For the purposes of paragraphs A.6.5.1 to A.6.5.3:
(a)
qDuoγ(t) is the Dispatch Quantity as a function of time for Generator
Unit, u, for Bid Offer Acceptance, o, in Imbalance Settlement Period,
γ;
37
A.6.5.5
(b)
qDAuoγ(t) is the Adjusted Dispatch Quantity as a function of time for
Generator Unit, u, for Bid Offer Acceptance, o, in Imbalance
Settlement Period, γ;
(c)
qDANFuoγ(t) is the Non-Firm Adjusted Dispatch Quantity as a function
of time for Generator Unit, u, for Bid Offer Acceptance, o, in
Imbalance Settlement Period, γ;
(d)
qFAQuγ(t) is the Firm Access Quantity as a function of time for
Generator Unit, u, in Imbalance Settlement Period, γ;
(e)
qBOURuiγ(t) is the Bid Offer Upper Range Quantity as a function of
time for Generator Unit, u, for Band, i, in Imbalance Settlement
Period, γ;
(f)
qBOLRuiγ(t) is the Bid Offer Lower Range Quantity as a function of
time for Generator Unit, u, for Band, i, in Imbalance Settlement
Period, γ;
(g)
qFPNuγ(t) is the Final Physical Notification Quantity as a function of
time for Generator Unit, u, in Imbalance Settlement Period, γ;
(h)
qAVAILOuγ(t) is the Outturn Availability Quantity as a function of time
for Generator Unit, u, in Imbalance Settlement Period, γ;
(i)
(o – 1) is for the previous Bid Offer Acceptance.
(j)
(i – 1) is for the previous Band when considering Bands in the positive
direction (i > 0);
(k)
(i + 1) is for the previous Band when considering Bands in the
negative direction (i < 0);
(l)
(o = 0) or (i = 0) is for the 0th value for the relevant aspect (i.e. the
implicit default value before an explicit Bid Offer Acceptance, o; the
value for Band, i, where i = 0).
The Market Operator shall calculate the Non-Firm Accepted Bid Quantity
(qABNFuoiγ(t)) as a function of time, for each Generator Unit, u, for each Bid
Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ, as
follows:
𝑞𝐴𝐵𝑁𝐹𝑢𝑜𝑖𝛾 (𝑡) = 𝑀𝑖𝑛(𝑞𝐵𝑂𝐴𝑁𝐹𝑢𝑜𝑖𝛾 (𝑡) ,0)
where:
(a)
qBOANFuoiγ(t) is the Non-Firm Accepted Bid Offer Quantity as a
function of time for Generator Unit, u, for Bid Offer Acceptance, o, for
Band, i, in Imbalance Settlement Period, γ.
A.6.5.6
The Market Operator shall calculate the Non-Firm Accepted Bid Quantity
(QABNFuoiγ) as an integrated quantity for the Imbalance Settlement Period γ,
for Generator Unit u, for Bid Offer Acceptance, o, for Band, i, for the
Imbalance Settlement Period, γ, by integrating the the associated function of
time the quantity Non-Firm Accepted Bid Quantity (qABNFuoiγ(t)) with respect
to time across the Imbalance Settlement Period, γ.
A.6.5.7
The provisions in section A.6.5 do not apply to an Interconnector Error Unit.
A.6.6
Calculation of Undelivered Quantities
38
Explanatory notes:
-
If a participant’s metered generation shows that they did not deliver their balancing
market order according to their dispatched quantity – the volume to which the
premium/discount is attributed should not include this undelivered volume;
-
Calculate the uninstructed imbalance volume on a unit for a period (different than the
imbalance component which includes instructed imbalances, this is the difference
between what the unit was instructed to do, and what they delivered).
-
Determine, from the orders accepted and the uninstructed imbalance volume on the
unit, the volume of the accepted orders, in whole or a fraction, which were not delivered
(i.e. for over-delivery, decs deemed not to have been delivered, for under-delivery, incs
deemed not to have been delivered).
-
Remove these volumes from the premium or discount component.
Explanatory Note
The intention of the equation below is as follows:
-
A.6.6.1
Calculate the total undelivered quantity, which is the difference between what the unit
was dispatched to do (QD) and what it actually did (QM). If this value is negative, it
means that QM was below QD, meaning it should have delivered more: therefore inc
offers may not have been delivered. If this value is positive, it means that QM was
above QD, meaning it should have delivered less: therefore dec bids may not have
been delivered.
The Market Operator shall calculate the Undelivered Quantity (QUNDELuγ)
for each Generator Unit, u, in Imbalance Settlement Period, γ, as follows:
𝑄𝑈𝑁𝐷𝐸𝐿𝑢𝛾 = 𝑄𝑀𝐿𝐹𝑢𝛾 − 𝑄𝐷𝐿𝐹𝑢𝛾
where:
(a)
QMLFuγ is the Loss-Adjusted Metered Quantity for Generator Unit, u,
in Imbalance Settlement Period, γ;
(b)
QDLFuγ is the Loss-Adjusted Dispatch Quantity for the Generator unit,
u, in Imbalance Settlement Period, γ.
A.6.6.2
Where the Undelivered Quantity has a positive value, the Market Operator
shall determine which of the Accepted Bid Quantities were not delivered, in
whole or in part, for each Generator Unit, u, in Imbalance Settlement Period,
γ, in accordance with paragraphs A.6.6.3 to A.6.6.5.
A.6.6.3
The Market Operator shall derive a ranked set of all Accepted Bid Quantities
for Generator Unit, u, in Imbalance Settlement Period, γ, in order of
increasing price. The Accepted Bid Quantity with the lowest price will be
allocated a rank number n = 1, the next lowest priced Accepted Bid Quantity
a rank number n = 2 and so on until all Accepted Bid Quantities have been
allocated a rank number. Where two or more Accepted Bid Quantities have
equal prices, they shall be ranked using a systematic process of random
selection which may include making small alterations to the submitted prices.
Any such amended prices will only be used for this purpose in the ranking
process.
Explanatory Note
The intention of the equations below is as follows:
-
In the first paragraph of this section, the total undelivered amount was calculated.
39
These equations are intended to overlay the total undelivered amount onto a stack
of the accepted bids to determine which of them were not delivered. It looks at each
bid in the stack, in price order.
A.6.6.4
-
If the volume of the undelivered quantity remaining to assign is larger than the
volume of the accepted bid being considered, it determines that all of that accepted
bid volume is undelivered. This is done in the first equation.
-
The second equation then reduces the volume of the undelivered quantity
remaining to assign after the assignment for the current order.
-
These two equations continue to be used for each bid in the stack in order, until the
last amount of the remaining undelivered quantity has been assigned: this is done
firstly in the first equation where the smaller volume of the bid or the remaining
undelivered is taken (small as in both of these should be negative quantities,
therefore the smallest negative quantity, the max, should be taken), this would be
like saying a bid quantity was partially undelivered. The second equation then
reduces the amount of remaining undelivered to zero or a negative number, such
that where it to be used for the next bid in the stack, the result of the first equation
would be zero.
-
The third line is an input to the process: for the first bid in the stack being
considered, all of the undelivered volume calculated earlier is remaining to be
assigned.
The Market Operator shall calculate the Undelivered Accepted Bid Quantity
(QABUNDELuoiγn) for each Generator Unit, u, for each Bid Offer Acceptance,
o, for each Band, i, in ascending order of each position, n, in the ranked set ,
in Imbalance Settlement Period, γ, as follows:
𝑄𝐴𝐵𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾𝑛 = 𝑀𝑖𝑛(𝑀𝑎𝑥(𝑄𝐴𝐵𝐿𝐹𝑢𝑜𝑖𝛾𝑛 , −𝑄𝑈𝑁𝐷𝐸𝐿𝑅𝑢𝛾(𝑛−1) ), 0)
𝑄𝑈𝑁𝐷𝐸𝐿𝑅𝑢𝛾𝑛 = 𝑄𝑈𝑁𝐷𝐸𝐿𝑅𝑢𝛾(𝑛−1) + 𝑄𝐴𝐵𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾𝑛
𝑄𝑈𝑁𝐷𝐸𝐿𝑅𝑢𝛾(𝑛=0) = 𝑄𝑈𝑁𝐷𝐸𝐿𝑢𝛾
This is done in ascending order of each position, n, in the ranked set .
where:
(a)
QABLFuoiγn is the Loss-Adjusted Accepted Bid Quantity for Generator
Unit, u, for Bid Offer Acceptance, o, for Band, i, in the ranked set at
rank, n, in Imbalance Settlement Period, γ;
(b)
QUNDELRuγn is the Remaining Undelivered Quantity for Generator
Unit, u, for the calculations in the ranked set at rank, n, in Imbalance
Settlement Period, γ;
(c)
QUNDELuγ is the Undelivered Quantity for Generator Unit, u, in
Imbalance Settlement Period, γ.
(d)
(n – 1) is for the previous item in the ranked set; and
(e)
(n = 0) is for the 0th item in the ranked set, i.e. where a calculation is
being performed on the first item in the ranked set, (n = 1), for which
there is no previous item.
Explanatory Note
The intention of the equation below is as follows:
-
Since the previous paragraph needed to work on bids in a certain order, subscript
n was used to determine that order. This ordering is not important for the
40
remaining settlement processes, so the value of the undelivered portion of
accepted bid quantity for GU, u, for BOA, o, in band, i, in period, gamma, is the
same as the value determined for the same u, o, i, and gamma, with the n
subscript.
A.6.6.5
The Market Operator shall calculate the Undelivered Accepted Bid Quantity
(QABUNDELuoiγ) for each Generator Unit, u, for each Bid Offer Acceptance,
o, for each Band, i, in Imbalance Settlement Period, γ, as follows:
𝑄𝐴𝐵𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾 = 𝑄𝐴𝐵𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾𝑛
where:
(a)
QABUNDELuoiγn is the Undelivered Accepted Bid Quantity for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, for position
in the rank set, n, in Imbalance Settlement Period, γ.
A.6.6.6
Where the Undelivered Quantity has a negative value, the Market Operator
shall determine which of the Accepted Offer Quantities were not delivered, in
whole or in part, for each Generator Unit, u, in Imbalance Settlement Period,
γ, in accordance with paragraphs A.6.6.7 to A.6.6.9.
A.6.6.7
The Market Operator shall derive a ranked set of all Accepted Offer
Quantities for Generator Unit, u, in Imbalance Settlement Period, γ, in order
of decreasing price. The Accepted Offer Quantity with the highest price will
be allocated a rank number n = 1, the next highest priced Accepted Offer
Quantity a rank number n = 2 and so on until all Accepted Offer Quantities
have been allocated a rank number. Where two or more Accepted Offer
Quantities have equal prices, they shall be ranked using a systematic
process of random selection which may include making small alterations to
the submitted prices. Any such amended prices will only be used for this
purpose in the ranking process.
Explanatory Note
The intention of the equations below is as follows:
-
A.6.6.8
This is the same as for earlier, but because of the sign of the total undelivered
quantity, offers are being considered rather than bids. This changes where we are
looking at max or min in the formulations: in the previous equations for decs,
because in the first equation we were firstly looking for the smallest volume of the
offer quantity or the remaining undelivered quantity, for decs the smallest of two
negative quantities in the max, for incs the smallest of two positive quantities is
the min.
The Market Operator shall calculate the Undelivered Accepted Offer Quantity
(QAOUNDELuoiγn) for each Generator Unit, u, for each Bid Offer Acceptance,
o, for each Band, i, in ascending order of each position, n, in the ranked set,
in Imbalance Settlement Period, γ, as follows:
𝑄𝐴𝑂𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾𝑛 = 𝑀𝑎𝑥(𝑀𝑖𝑛(𝑄𝐴𝑂𝐿𝐹𝑢𝑜𝑖𝛾𝑛 , −𝑄𝑈𝑁𝐷𝐸𝐿𝑅𝑢𝛾(𝑛−1) ), 0)
𝑄𝑈𝑁𝐷𝐸𝐿𝑅𝑢𝛾𝑛 = 𝑄𝑈𝑁𝐷𝐸𝐿𝑅𝑢𝛾(𝑛−1) + 𝑄𝐴𝑂𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾𝑛
𝑄𝑈𝑁𝐷𝐸𝐿𝑅𝑢𝛾(𝑛=0) = 𝑄𝑈𝑁𝐷𝐸𝐿𝑢𝛾
41
This is done in ascending order of each position, n, in the ranked set.
where:
A.6.6.9
(a)
QAOLFuoiγn is the Loss-Adjusted Accepted Offer Quantity for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in the
ranked set at rank, n, in Imbalance Settlement Period, γ;
(b)
QUNDELRuγn is the Remaining Undelivered Quantity for Generator
Unit, u, for the calculations in the ranked set at rank, n, in Imbalance
Settlement Period, γ;
(c)
QUNDELuγ is the Undelivered Quantity for Generator Unit, u, in
Imbalance Settlement Period, γ.
(d)
(n – 1) is for the previous item in the ranked set; and
(e)
(n = 0) is for the 0th item in the ranked set, i.e. where a calculation is
being performed on the first item in the ranked set, (n = 1), for which
there is no previous item.
The Market Operator shall calculate the Undelivered Accepted Offer Quantity
(QAOUNDELuoiγ) for each Generator Unit, u, for each Bid Offer Acceptance,
o, for each Band, i, in Imbalance Settlement Period, γ, as follows:
𝑄𝐴𝑂𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾 = 𝑄𝐴𝑂𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾𝑛
where:
(a)
QAOUNDELuoiγn is the Undelivered Accepted Offer Quantity for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, for position
in the rank set, n, in Imbalance Settlement Period, γ.
Explanatory Note
Intention of paragraphs below is as follows:
-
As stated earlier, to fully consider bias and undelivered quantities, the IEU needs to
consider these in the premium and discount component. This needs to be done by
stating that although the biased and undelivered quantities are calculated for the
ICRP (because they are the unit with the Accepted Offers and Accepted Bids, and
FPN, which are used to calculate the quantities), they are taken forward through the
IEU for settlement.
A.6.6.10 The provisions in paragraphs A.6.6.1 to A.6.6.9 do not apply to an
Interconnector Error Unit.
A.6.6.11 The Market Operator shall:
(a)
assign the Undelivered Accepted Offer Quantities and Undelivered
Accepted Bid Quantities, QAOUNDELuoiγ and QABUNDELuoiγ,
calculated in accordance with paragraphs A.6.6.1 to A.6.6.9 for an
Interconnector Residual Capacity Unit, u, to the relevant
Interconnector Error Unit, u; and
(b)
set the values of the quantities referred to in paragraph (a) for the
Interconnector Residual Capacity Unit to zero,
for the purposes of any processes using these quantities.
42
A.6.7
Calculation of Biased Quantities
Explanatory notes
-
If a participant’s FPN is biased, with reference to its ex-ante position, in a direction
which increases the volume to which the premium/discount is attributed (i.e. PN
biased below ex-ante position for incs, above ex-ante position for decs) – the
volume to which the premium/discount is attributed should not include this
component of the volume. This is because the biased volume was already settled in
the ex-ante markets, it was only calculated in the Balancing Market because the PN
was biased versus the ex-ante position, therefore to ensure it isn’t double counted
we must remove it from the balancing market volumes calculated.
-
Calculate the difference between the ex-ante quantity (EAQ) of the unit and the PN
which is intended to represent that position.
-
Determine, from the orders accepted and the difference between the ex-ante
position of the unit and the PN, if there are quantities of the accepted orders, in
whole or a fraction, which result from a bias (i.e. if the PN was lower than the EAQ it
was intended to represent, then some inc orders could be biased. If the PN was
higher than the EAQ it was intended to represent, then some dec orders could be
biased).
-
Remove these volumes from the premium or discount component.
Explanatory Note
The intention of the equations in section A.6.7 is as follows:
A.6.7.1
-
This is the same process as for determining which balancing market quantities, of
fractions of those quantities, are undelivered. It overlays the total onto a stack of
orders, which are incs or decs depending on whether the bias value is positive or
negative.
-
The price order of the stack is different. Undelivered quantities look at prices from
high to low for incs, low to high for decs, to capture those which are most
“expensive” and deeming them undelivered first. This is based on logic that the
quantities nearest the dispatch quantity would be most expensive, as actions are
taken in order from least to most expensive and QD should be the final point of
actions taken. Biased quantities look at prices from low to high for incs, high to low
for decs, to capture those which are “cheapest” and deeming them biased first. This
is based on the logic that the FPN is the start point for actions taken, and therefore
actions nearest FPN which could be biased would be the cheapest.
The Market Operator shall calculate the Biased Quantity (QBIASuγ) for each
Generator Unit, u, in Imbalance Settlement Period, γ, as follows:
𝑄𝐵𝐼𝐴𝑆𝑢𝛾 = 𝑄𝐸𝑋𝑢𝛾 − 𝑄𝐹𝑃𝑁𝐿𝐹𝑢𝛾
where:
(a)
QEXuγ is the Ex-Ante Quantity for Generator Unit, u, in Imbalance
Settlement Period, γ, as calculated under section A.5.2;
(b)
QFPNLFuγ is the Loss-Adjusted Final Physical Notification Quantity
for the Generator unit, u, in Imbalance Settlement Period, γ.
A.6.7.2
Where the Biased Quantity has a positive value, the Market Operator shall
determine which of the Accepted Offer Quantities were biased, in whole or in
part, for each Generator Unit, u, in Imbalance Settlement Period, γ, in
accordance with paragraphs A.6.7.3 to A.6.7.6.
A.6.7.3
The Market Operator shall derive a ranked set of all Accepted Offer
Quantities for Generator Unit, u, in Imbalance Settlement Period, γ, in order
of increasing price. The Accepted Offer Quantity with the lowest price will be
43
allocated a rank number n = 1, the next lowest priced Accepted Offer
Quantity a rank number n = 2 and so on until all Accepted Offer Quantities
have been allocated a rank number. Where two or more Accepted Offer
Quantities have equal prices, they shall be ranked using a systematic
process of random selection which may include making small alterations to
the submitted prices. Any such amended prices will only be used for this
purpose in the ranking process.
A.6.7.4
The Market Operator shall calculate the Biased Accepted Offer Quantity
(QAOBIASuoiγn) for each Generator Unit, u, for each Bid Offer Acceptance, o,
for each Band, i, in ascending order of each position, n, in the ranked set, in
Imbalance Settlement Period, γ, as follows:
𝑄𝐴𝑂𝐵𝐼𝐴𝑆𝑢𝑜𝑖𝛾𝑛 = 𝑀𝑎𝑥(𝑀𝑖𝑛(𝑄𝐴𝑂𝐿𝐹𝑢𝑜𝑖𝛾𝑛 , 𝑄𝐵𝐼𝐴𝑆𝑅𝑢𝛾(𝑛−1) ), 0)
𝑄𝐵𝐼𝐴𝑆𝑅𝑢𝛾𝑛 = 𝑄𝐵𝐼𝐴𝑆𝑅𝑢𝛾(𝑛−1) − 𝑄𝐴𝑂𝐵𝐼𝐴𝑆𝑢𝑜𝑖𝛾𝑛
𝑄𝐵𝐼𝐴𝑆𝑅𝑢𝛾(𝑛=0) = 𝑄𝐵𝐼𝐴𝑆𝑢𝛾
This is done in ascending order of each position, n, in the ranked set.
where:
A.6.7.5
(a)
QAOLFuoiγn is the Loss-Adjusted Accepted Offer Quantity for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in the
ranked set at rank, n, in Imbalance Settlement Period, γ;
(b)
QBIASRuγn is the Remaining Biased Quantity for Generator Unit, u,
for the calculations in the ranked set at rank, n, in Imbalance
Settlement Period, γ;
(c)
QBIASuγ is the Biased Quantity for Generator Unit, u, in Imbalance
Settlement Period, γ;
(d)
(n – 1) is for the previous item in the ranked set; and
(e)
(n = 0) is for the 0th item in the ranked set, i.e. where a calculation is
being performed on the first item in the ranked set, (n = 1), for which
there is no previous item.
The Market Operator shall calculate the Biased Accepted Offer Quantity
(QAOBIASuoiγ) for each Generator Unit, u, for each Bid Offer Acceptance, o,
for each Band, i, in Imbalance Settlement Period, γ, as follows:
𝑄𝐴𝑂𝐵𝐼𝐴𝑆𝑢𝑜𝑖𝛾 = 𝑄𝐴𝑂𝐵𝐼𝐴𝑆𝑢𝑜𝑖𝛾𝑛
where:
(a)
A.6.7.6
QAOBIASuoiγn is the Biased Accepted Bid Quantity for Generator Unit,
u, for Bid Offer Acceptance, o, for Band, i, for position in the rank set,
n, in Imbalance Settlement Period, γ.
Where the Biased Quantity has a negative value, the Market Operator shall
determine which of the Accepted Bid Quantities were biased, in whole or in
part, for each Generator Unit, u, in Imbalance Settlement Period, γ, in
accordance with paragraphs A.6.7.7 to A.6.7.9.
44
A.6.7.7
The Market Operator shall derive a ranked set of all Accepted Bid Quantities
for Generator Unit, u, in Imbalance Settlement Period, γ, in order of
decreasing price. The Accepted Bid Quantity with the highest price will be
allocated a rank number n = 1, the next highest priced Accepted Bid Quantity
a rank number n = 2 and so on until all Accepted Bid Quantities have been
allocated a rank number. Where two or more Accepted Bid Quantities have
equal prices, they shall be ranked using a systematic process of random
selection which may include making small alterations to the submitted prices.
Any such amended prices will only be used for this purpose in the ranking
process.
A.6.7.8
The Market Operator shall calculate the Biased Accepted Bid Quantity
(QABBIASuoiγn) for each Generator Unit, u, for each Bid Offer Acceptance, o,
for each Band, i, in ascending order of each position, n, in the ranked set, in
Imbalance Settlement Period, γ, as follows:
𝑄𝐴𝐵𝐵𝐼𝐴𝑆𝑢𝑜𝑖𝛾𝑛 = 𝑀𝑖𝑛(𝑀𝑎𝑥(𝑄𝐴𝐵𝐿𝐹𝑢𝑜𝑖𝛾𝑛 , 𝑄𝐵𝐼𝐴𝑆𝑅𝑢𝛾(𝑛−1) ), 0)
𝑄𝐵𝐼𝐴𝑆𝑅𝑢𝛾𝑛 = 𝑄𝐵𝐼𝐴𝑆𝑅𝑢𝛾(𝑛−1) − 𝑄𝐴𝐵𝐵𝐼𝐴𝑆𝑢𝑜𝑖𝛾𝑛
𝑄𝐵𝐼𝐴𝑆𝑅𝑢𝛾(𝑛=0) = 𝑄𝐵𝐼𝐴𝑆𝑢𝛾
This is done in ascending order of each position, n, in the ranked set.
where:
A.6.7.9
(a)
QABLFuoiγn is the Loss-Adjusted Accepted Bid Quantity for Generator
Unit, u, for Bid Offer Acceptance, o, for Band, i, in the ranked set at
rank, n, in Imbalance Settlement Period, γ;
(b)
QBIASRuγn is the Remaining Biased Quantity for Generator Unit, u,
for the calculations in the ranked set at rank, n, in Imbalance
Settlement Period, γ;
(c)
QBIASuγ is the Biased Quantity for Generator Unit, u, in Imbalance
Settlement Period, γ.
(d)
(n – 1) is for the previous item in the ranked set;
(e)
(n = 0) is for the 0th item in the ranked set, i.e. where a calculation is
being performed on the first item in the ranked set, (n = 1), for which
there is no previous item.
The Market Operator shall calculate the Biased Accepted Bid Quantity
(QABBIASuoiγ) for each Generator Unit, u, for each Bid Offer Acceptance, o,
for each Band, i, in Imbalance Settlement Period, γ, as follows:
𝑄𝐴𝐵𝐵𝐼𝐴𝑆𝑢𝑜𝑖𝛾 = 𝑄𝐴𝐵𝐵𝐼𝐴𝑆𝑢𝑜𝑖𝛾𝑛
where:
(a)
QABBIASuoiγn is the Biased Accepted Bid Quantity for Generator Unit,
u, for Bid Offer Acceptance, o, for Band, i, for position in the rank set,
n, in Imbalance Settlement Period, γ.
A.6.7.10 The provisions of section A.6.7 do not apply to any Generator Unit which is
an Autoproducer.
45
A.6.7.11 The provisions of paragraphs A.6.7.1 to A.6.7.9 do not apply to any unit
which is an Interconnector Error Unit.
A.6.7.12 The Market Operator shall:
(a)
assign the Biased Accepted Offer Quantities and Biased Accepted
Bid Quantities, QAOBIASuoiγ and QABBIASuoiγ, calculated in
accordance with paragraphs A.6.7.2 to A.6.7.9 for an Interconnector
Residual Capacity Unit, u, to the relevant Interconnector Error Unit, u;
and
(b)
set the values of the quantities referred to in paragraph (a) for the
Interconnector Residual Capacity Unit to zero,
for the purposes of any processes using these quantities.
A.6.8
Calculation of Premium and Discount Component Payments
Explanatory Note
The intention of the equations below is as follows:
-
In all the previous sections, and in a section to come, the quantities to be considered
as part of the premium and discount cash flow calculation have been determined.
This section applies the premium (if the bid offer price is greater than the imbalance
settlement price) and the discount (if the bid offer price is less than the imbalance
settlement price) to the correct volumes. Consider that the imbalance component
already pays the imbalance settlement price, so this component only needs to pay
the difference between the bid offer price and imbalance settlement price.
-
The premium is paid to accepted offer quantities which are:
-
-
A.6.8.1
o
Delivered (therefore subtract undelivered);
o
Not due to TOTSO (therefore subtract TOTSO);
o
Not due to bias (therefore subtract BIAS); and
o
Not paid a different price (therefore subtract OPO, offer price only).
The discount is paid to accepted bid quantities which are:
o
Delivered (therefore subtract undelivered);
o
Not due to TOTSO (therefore subtract TOTSO);
o
Not due to bias (therefore subtract BIAS);
o
Firm (therefore subtract non-firm, NF); and
o
Not paid a different price (therefore subtract BPO, bid price only, and CURL,
curtailment).
All of these quantities might cover the same volume, e.g. a TOTSO volume could also
be undelivered. Therefore to ensure against double-counting the same volume, the
largest of the values for the given BOA, o, and band, i, is taken: if there are volumes
in the same band (output range) for the same BOA, they are the same volume. The
largest value is found by taking the max of the positive quantity values for the
premium, the min of the negative quantity values for the discount.
The Market Operator shall calculate Premium and Discount Component
Payments for each Generator Unit, u, and each Imbalance Settlement
Period, γ, as follows:
46
𝐶𝑃𝑅𝐸𝑀𝐼𝑈𝑀𝑢𝛾
= ∑ ∑ (𝑀𝑎𝑥(𝑃𝐵𝑂𝑢𝛽𝑜𝑖𝛾 − 𝑃𝐼𝑀𝐵𝛾 , 0)
𝑜
𝑖
× (𝑄𝐴𝑂𝐿𝐹𝑢𝑜𝑖𝛾
− 𝑀𝑎𝑥(𝑄𝐴𝑂𝑂𝑃𝑂𝐿𝐹𝑢𝑜𝑖𝛾 , 𝑄𝐴𝑂𝐵𝐼𝐴𝑆𝑢𝑜𝑖𝛾 , 𝑄𝐴𝑂𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾 , 𝑄𝐴𝑂𝑇𝑂𝑇𝑆𝑂𝐿𝐹𝑢𝑜𝑖𝛾 )))
𝐶𝐷𝐼𝑆𝐶𝑂𝑈𝑁𝑇𝑢𝛾
= ∑ ∑ (𝑀𝑖𝑛(𝑃𝐵𝑂𝑢𝛽𝑜𝑖𝛾 − 𝑃𝐼𝑀𝐵𝛾 , 0)
𝑜
𝑖
× (𝑄𝐴𝐵𝐿𝐹𝑢𝑜𝑖𝛾
− 𝑀𝑖𝑛(𝑄𝐴𝐵𝐵𝑃𝑂𝐿𝐹𝑢𝑜𝑖𝛾 , 𝑄𝐴𝐵𝐵𝐼𝐴𝑆𝑢𝑜𝑖𝛾 , 𝑄𝐴𝐵𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾 , 𝑄𝐴𝐵𝑁𝐹𝐿𝐹𝑢𝑜𝑖𝛾 , 𝑄𝐴𝐵𝐶𝑈𝑅𝐿𝐿𝐹𝑢𝑜𝑖𝛾 ,
𝑄𝐴𝐵𝑇𝑂𝑇𝑆𝑂𝐿𝐹𝑢𝑜𝑖𝛾 )))
where:
(a)
PIMBγ is the Imbalance Settlement Price in Imbalance Settlement
Period, γ[, as calculated in section on Imbalance Pricing];
(b)
PBOuβoiγ is the Bid Offer Price for each individual Accepted Bid
Quantity and Accepted Offer Quantity for Generator Unit, u, time
stamped, β, as the last one submitted by the relevant Participant
before Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement
Period, γ, determined in accordance with section A.6.3;
(c)
QAOLFuoiγ is the Loss-Adjusted Accepted Offer Quantity for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in
Imbalance Settlement Period, γ, calculated in accordance with
section A.6.1;
(d)
QABLFuoiγ is the Loss-Adjusted Accepted Bid Quantity for Generator
Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance
Settlement Period, γ, calculated in accordance with section A.6.1;
(e)
QAOTOTSOLFuoiγ is the Loss-Adjusted Trade Opposite TSO
Accepted Offer Quantity for Generator Unit, u, for Bid Offer
Acceptance, o, for Band, i, in Imbalance Settlement Period, γ,
calculated in accordance with section A.6.4;
(f)
QABTOTSOLFuoiγ is the Loss-Adjusted Trade Opposite TSO
Accepted Bid Quantity for Generator Unit, u, for Bid Offer
Acceptance, o, for Band, i, in Imbalance Settlement Period, γ,
calculated in accordance with section A.6.4;
(g)
QABNFLFuoiγ is the Loss-Adjusted Non-Firm Accepted Bid Quantity
for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in
Imbalance Settlement Period, γ, calculated in accordance with
section A.6.5;
(h)
QAOUNDELuoiγ is the Undelivered Accepted Offer Quantity for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in
Imbalance Settlement Period, γ, calculated in accordance with
section A.6.6;
(i)
QABUNDELuoiγ is the Undelivered Accepted Bid Quantity for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in
47
Imbalance Settlement Period, γ, calculated in accordance with
section A.6.6;
A.6.8.2
A.7
(j)
QAOBIASuoiγ is the Biased Accepted Offer Quantity for Generator
Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance
Settlement Period, γ, calculated in accordance with section A.6.7;
(k)
QABBIASuoiγ is the Biased Accepted Bid Quantity for Generator Unit,
u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement
Period, γ, calculated in accordance with section A.6.7;
(l)
QABCURLLFuoiγ is the Loss-Adjusted Curtailment Accepted Bid
Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band,
i, in Imbalance Settlement Period, γ, calculated in accordance with
section A.8.1;
(m)
QAOOPOLFuoiγ is the Loss-Adjusted Offer Price Only Accepted Bid
Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band,
i, in Imbalance Settlement Period, γ, calculated in accordance with
section A.7.1;
(n)
QABBPOLFuoiγ is the Loss-Adjusted Bid Price Only Accepted Bid
Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band,
i, in Imbalance Settlement Period, γ, calculated in accordance with
section A.7.1.
The provisions in paragraph A.6.8.1 do not apply to any unit which is:
(a)
An Assetless Unit;
(b)
A Trading Unit;
(c)
An Autonomous Generator Unit.
ACCEPTED OFFERS BELOW PHYSICAL NOTIFICATION, AND
ACCEPTED
BIDS
ABOVE
PHYSICAL
NOTIFICATION,
QUANTITIES, PAYMENTS AND CHARGES
Explanatory notes
-
Functionality for determining when the refined approach is to be used, of applying the
bid or offer price only to a BOA where that volume is due to the TSO undoing an
earlier BOA, i.e.: incs from a point below the PN, and decs from a point above the
PN.
-
Calculating the volume to which the refined approach applies and removing this from
the premium component for incs.
-
Calculating the volume to which the refined approach applies and removing this from
the discount component for decs.
-
Applying the correct offer or bid price to the volume to which the refined approach
applies for incs and decs respectively.
-
The volume is removed from the premium/discount component by explicitly
subtracting the volume and imbalance component by implicitly applying the negative
of the imbalance settlement price to the volume to which the refined approach is
applied to counter the positive imbalance settlement price on that volume in the
imbalance component, and then the relevant bid or offer price is applied to the
volume.
48
A.7.1
Calculation of Accepted Offers Below Physical Notification and
Accepted Bids Above Physical Notification Quantities
Explanatory Note
The intention of the equations in section A.7.1 is as follows:
-
This is the same as the formulation of qBOA calculation but tweaked to isolate only
those volumes which are being sought for this different treatment.
-
In this case, the volumes sought are those inc offers accepted which were from a
point below the FPN, and those dec offers accepted which were from a point above
the FPN. This amounts to an undo, e.g. if an inc offer was accepted through one
dispatch instruction (from calculate qBOA from FPN to qD1), but then another
dispatch instruction was issued to have the unit output lower than was intended by
the original inc, a dec bid would be calculated from a start point above the FPN (from
qD1 to qD2), this would be an undo and the detailed design said this should only be
remunerated at the bid-offer price, not the better of the bid-offer price and imbalance
settlement price.
-
How these volumes are isolated are through the second line of the conditions for incs
and decs where:
-
A.7.1.1
o
the dispatch quantity for the current order is stopped at the FPN quantity for
incs when the dispatch quantity is rising from a lower level up to the FPN
quantity (by taking the minimum); and
o
the dispatch quantity for the current order is stopped at the FPN quantity for
decs when the dispatch quantity is falling from a higher level down to the
FPN quantity.
All the other lines are as per qBOA calculation.
The Market Operator shall calculate two values for the Price Only Accepted
Bid Offer Quantity (qBOAPOuoiγ(t)) as a function of time, for each Generator
Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in Imbalance
Settlement Period, γ, calculating separately one value for all Incs resulting
from the Bid Offer Acceptance and one value for all Decs resulting from the
Bid Offer Acceptance as follows:
(a)
For i > 0:
𝑞𝐵𝑂𝐴𝑃𝑂𝑢𝑜𝑖𝛾 (𝑡)
= 𝑀𝑎𝑥{𝑀𝑖𝑛{𝑞𝐷𝐴𝑢𝑜𝛾 (𝑡), 𝑞𝐵𝑂𝑈𝑅𝑢𝑖𝛾 (𝑡)}, 𝑞𝐵𝑂𝑈𝑅𝑢(𝑖−1)𝛾 (𝑡)}
− 𝑀𝑎𝑥{𝑀𝑖𝑛{𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡), 𝑞𝐵𝑂𝑈𝑅𝑢𝑖𝛾 (𝑡)}, 𝑞𝐵𝑂𝑈𝑅𝑢(𝑖−1)𝛾 (𝑡)}
(b)
For i < 0:
𝑞𝐵𝑂𝐴𝑃𝑂𝑢𝑜𝑖𝛾 (𝑡)
= 𝑀𝑖𝑛{𝑀𝑎𝑥{𝑞𝐷𝐴𝑢𝑜𝛾 (𝑡), 𝑞𝐵𝑂𝐿𝑅𝑢𝑖𝛾 (𝑡)}, 𝑞𝐵𝑂𝐿𝑅𝑢(𝑖+1)𝛾 (𝑡)}
− 𝑀𝑖𝑛{𝑀𝑎𝑥{𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡), 𝑞𝐵𝑂𝐿𝑅𝑢𝑖𝛾 (𝑡)}, 𝑞𝐵𝑂𝐿𝑅𝑢(𝑖+1)𝛾 (𝑡)}
A.7.1.2
When calculating the value for the Price Only Accepted Bid Offer Quantity
(qBOAPOuoiγ(t)) for the Incs resulting from the Bid Offer Acceptance, the
Market Operator shall calculate the relevant variables as follows:
𝑞𝐷𝐴𝑢𝑜𝛾 (𝑡) = 𝑞𝐷𝐴𝑃𝑂𝑢𝑜𝛾 (𝑡)
49
𝑞𝐷𝐴𝑃𝑂𝑢𝑜𝛾 (𝑡) = 𝑀𝑖𝑛 (𝑀𝑎𝑥 (𝑞𝐷𝑢𝑜𝛾 (𝑡), 𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡)) , 𝑞𝐹𝑃𝑁𝑢𝛾 (𝑡))
𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡) = 𝑞𝐷𝑢(𝑜−1)𝛾 (𝑡)
𝑞𝐷𝑢(𝑜=0)𝛾 (𝑡) = 𝑞𝐹𝑃𝑁𝑢𝛾 (𝑡)
𝑞𝐵𝑂𝑈𝑅𝑢(𝑖=0)𝛾 (𝑡) = 0
𝑞𝐵𝑂𝐿𝑅𝑢(𝑖=0)𝛾 (𝑡) = 0
A.7.1.3
When calculating the value for the Price Only Accepted Bid Offer Quantity
(qBOAPOuoiγ(t)) for the Decs resulting from the Bid Offer Acceptance, the
Market Operator shall calculate the relevant variables as follows:
𝑞𝐷𝐴𝑢𝑜𝛾 (𝑡) = 𝑞𝐷𝐴𝑃𝑂𝑢𝑜𝛾 (𝑡)
𝑞𝐷𝐴𝑃𝑂𝑢𝑜𝛾 (𝑡) = 𝑀𝑎𝑥 (𝑀𝑖𝑛 (𝑞𝐷𝑢𝑜𝛾 (𝑡), 𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡)) , 𝑞𝐹𝑃𝑁𝑢𝛾 (𝑡))
𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡) = 𝑞𝐷𝑢(𝑜−1)𝛾 (𝑡)
𝑞𝐷𝑢(𝑜=0)𝛾 (𝑡) = 𝑀𝑖𝑛 (𝑞𝐹𝑃𝑁𝑢𝛾 (𝑡), 𝑞𝐴𝑉𝐴𝐼𝐿𝑂𝑢𝛾 (𝑡))
𝑞𝐵𝑂𝑈𝑅𝑢(𝑖=0)𝛾 (𝑡) = 0
𝑞𝐵𝑂𝐿𝑅𝑢(𝑖=0)𝛾 (𝑡) = 0
A.7.1.4
For the purposes of paragraphs A.7.1.1 to A.7.1.3:
(a)
qDuoγ(t) is the Dispatch Quantity as a function of time for Generator
Unit, u, for Bid Offer Acceptance, o, in Imbalance Settlement Period,
γ;
(b)
qDAuoγ(t) is the Adjusted Dispatch Quantity as a function of time for
Generator Unit, u, for Bid Offer Acceptance, o, in Imbalance
Settlement Period, γ;
(c)
qDAPOuoγ(t) is the Price Only Adjusted Dispatch Quantity as a
function of time for Generator Unit, u, for Bid Offer Acceptance, o, in
Imbalance Settlement Period, γ;
(d)
qBOURuiγ(t) is the Bid Offer Upper Range Quantity as a function of
time for Generator Unit, u, for Band, i, in Imbalance Settlement
Period, γ;
(e)
qBOLRuiγ(t) is the Bid Offer Lower Range Quantity as a function of
time for Generator Unit, u, for Band, i, in Imbalance Settlement
Period, γ;
(f)
qFPNuγ(t) is the Final Physical Notification Quantity as a function of
time for Generator Unit, u, in Imbalance Settlement Period, γ;
(g)
qAVAILOuγ(t) is the Outturn Availability Quantity as a function of time
for Generator Unit, u, in Imbalance Settlement Period, γ;
50
A.7.1.5
(h)
(o – 1) is for the previous Bid Offer Acceptance;
(i)
(i – 1) is for the previous Band when considering Bands in the positive
direction (i > 0);
(j)
(i + 1) is for the previous Band when considering Bands in the
negative direction (i < 0);
(k)
(o = 0) or (i = 0) is for the 0th value for the relevant aspect (i.e. the
implicit default value before an explicit Bid Offer Acceptance, o; the
value for Band, i, where i = 0).
The Market Operator shall calculate the Offer Price Only Accepted Offer
Quantity (qAOOPOuoiγ(t)) as a function of time, and the Bid Price Only
Accepted Bid Quantity (qABBPOuoiγ(t)) as a function of time, for each
Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in
Imbalance Settlement Period, γ, as follows:
𝑞𝐴𝑂𝑂𝑃𝑂𝑢𝑜𝑖𝛾 (𝑡) = 𝑀𝑎𝑥(𝑞𝐵𝑂𝐴𝑃𝑂𝑢𝑜𝑖𝛾 (𝑡) 𝑓𝑜𝑟 𝐼𝑛𝑐𝑠, 0)
𝑞𝐴𝐵𝐵𝑃𝑂𝑢𝑜𝑖𝛾 (𝑡) = 𝑀𝑖𝑛(𝑞𝐵𝑂𝐴𝑃𝑂𝑢𝑜𝑖𝛾 (𝑡) 𝑓𝑜𝑟 𝐷𝑒𝑐𝑠, 0)
where:
(a)
qBOAPOuoiγ(t) is the Price Only Accepted Bid Offer Quantity as a
function of time for Generator Unit, u, for Bid Offer Acceptance, o, for
Band, i, in Imbalance Settlement Period, γ.
A.7.1.6
The Market Operator shall calculate the Offer Price Only Accepted Offer
Quantity (QAOOPOuoiγ) as an integrated period quantity, and the Bid Price
Only Accepted Bid Quantity (QABBPOuoiγ) for Generator Unit, u, for Bid Offer
Acceptance, o, for Band, i, in Imbalance Settlement Period, γby integrating
the associated function of time Offer Price Only Accepted Offer Quantity
(qAOOPOuoiγ(t)) and Bid Price Only Accepted Bid Quantity qABBPOuoiγ(t))
over the Imbalance Settlement Period, γ.
A.7.2
Calculation of Accepted Offers Below Physical Notification and
Accepted Bids Above Physical Notification Payments and Charges
Explanatory Note
The intention of the equations below is as follows:
-
The bid-offer price should be applied to the undo volumes as determined in the
previous section, which have been delivered;
-
Since the imbalance component applies the imbalance settlement price to the volume
already, this is countered by applying the negative of the imbalance settlement price
to the volume. This is why there is a “-PIMB” term, and this has the effect of
“removing” the undo volume from the imbalance component.
-
The Bid Offer price is then also applied to the volume. This means that, since the
volume is implicitly removed from the imbalance component as explained by the
previous bullet point, and is explicitly removed from the premium/discount component
as explained in section A.6.8, there is no price applied to it in any other section, so
the application of the bid offer price in this equation means it is only remunerated at
the bid offer price.
-
For decs, the same volume might be an undo quantity as calculated in this section,
and a curtailment quantity. Therefore only the amount of the undo quantity which is
not a curtailment quantity gets settled in this way. The amount which is a curtailment
quantity gets settled in the next section.
51
A.7.2.1
The Market Operator shall calculate the Offer Price Only Accepted Offer
Payment or Charge (CAOOPOuγ) and the Bid Price Only Accepted Bid
Payment or Charge (CABBPOuγ) for each Generator Unit, u, in each
Imbalance Settlement Period, γ, as follows:
𝐶𝐴𝑂𝑂𝑃𝑂𝑢𝛾 = ∑ ∑ ((𝑃𝐵𝑂𝑢𝛽𝑜𝑖𝛾 − 𝑃𝐼𝑀𝐵𝛾 )
𝑜
𝑖
× 𝑀𝑎𝑥(𝑄𝐴𝑂𝑂𝑃𝑂𝐿𝐹𝑢𝑜𝑖𝛾 − 𝑄𝐴𝑂𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾 , 0))
𝐶𝐴𝐵𝐵𝑃𝑂𝑢𝛾 = ∑ ∑ ((𝑃𝐵𝑂𝑢𝛽𝑜𝑖𝛾 − 𝑃𝐼𝑀𝐵𝛾 )
𝑜
𝑖
× 𝑀𝑖𝑛(𝑄𝐴𝐵𝐵𝑃𝑂𝐿𝐹𝑢𝑜𝑖𝛾
− 𝑀𝑖𝑛(𝑄𝐴𝐵𝐶𝑈𝑅𝐿𝐿𝐹𝑢𝑜𝑖𝛾 , 𝑄𝐴𝐵𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾 ), 0))
where:
A.7.2.2
(a)
PIMBγ is the Imbalance Settlement Price in Imbalance Settlement
Period, γ[, as calculated in section on Imbalance Pricing];
(b)
PBOuβoiγ is the Bid Offer Price for each individual Accepted Bid
Quantity and Accepted Offer Quantity for Generator Unit, u, time
stamped, β, as the last one submitted by the relevant Participant
before Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement
Period, γ;
(c)
QAOOPOLFuoiγ is the Loss-Adjusted Offer Price Only Accepted Bid
Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band,
i, in Imbalance Settlement Period, γ;
(d)
QABBPOLFuoiγ is the Loss-Adjusted Bid Price Only Accepted Bid
Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band,
i, in Imbalance Settlement Period, γ;
(e)
QAOUNDELuoiγ is the Undelivered Accepted Offer Quantity for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in
Imbalance Settlement Period, γ;
(f)
QABCURLLFuoiγ is the Loss-Adjusted Curtailment Accepted Bid
Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band,
i, in Imbalance Settlement Period, γ;
(g)
QABUNDELuoiγ is the Undelivered Accepted Bid Quantity for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in
Imbalance Settlement Period, γ.
The provisions in section A.7 do not apply to any unit which is:
(a)
An Assetless Unit;
(b)
A Trading Unit;
(c)
An Interconnector Error Unit;
(d)
An Autonomous Generator Unit.
52
A.8
CURTAILMENT QUANTITIES, PRICES AND CHARGES
Explanatory notes
A.8.1
-
Functionality for determining the situations when the calculations for curtailed
volumes are needed, depending on when a dispatch instruction is issued with a
curtailment flag.
-
Calculating the curtailed volume for a unit when the situation requires this calculation,
and removing this from the discount component for decs.
-
If the situation arises where the refined approach to decs coincides with the
curtailment volume, remove the curtailed volume from the volume receiving the bid
price under the refined approach.
-
Applying the curtailment price to the curtailed dec volume.
Calculation of Curtailment Quantities
Explanatory Note
The intention of the equations in section A.8.1 is as follows:
A.8.1.1
-
This is the same as a qBOA calculation but isolating only those quantities which are
due to curtailment.
-
Curtailment is only ever a decremental quantity, therefore only inputs for decs apply.
-
How this is done is in the second line, by having a dispatch curve to follow which is
different to the previous dispatch curve only when the dispatch instruction to result in
that BOA had a curtailment flag. Otherwise, the dispatch curve for this calculation will
be the same as the previous dispatch curve, meaning when the inputs come to Parts
(a) and (b), a value of zero should always result. A non-zero value should only result
when the DI has a curtailment flag;
-
All other lines are as per qBOA calculation.
The Market Operator shall calculate the Curtailment Accepted Bid Offer
Quantity (qBOACURLuoiγ(t)) as a function of time for each Generator Unit, u,
for all Decs resulting from each Bid Offer Acceptance, o, for each Band, i, in
Imbalance Settlement Period, γ, as follows:
(a)
For i > 0:
𝑞𝐵𝑂𝐴𝐶𝑈𝑅𝐿𝑢𝑜𝑖𝛾 (𝑡)
= 𝑀𝑎𝑥{𝑀𝑖𝑛{𝑞𝐷𝐴𝑢𝑜𝛾 (𝑡), 𝑞𝐵𝑂𝑈𝑅𝑢𝑖𝛾 (𝑡)}, 𝑞𝐵𝑂𝑈𝑅𝑢(𝑖−1)𝛾 (𝑡)}
− 𝑀𝑎𝑥{𝑀𝑖𝑛{𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡), 𝑞𝐵𝑂𝑈𝑅𝑢𝑖𝛾 (𝑡)}, 𝑞𝐵𝑂𝑈𝑅𝑢(𝑖−1)𝛾 (𝑡)}
(b)
For i < 0:
𝑞𝐵𝑂𝐴𝐶𝑈𝑅𝐿𝑢𝑜𝑖𝛾 (𝑡)
= 𝑀𝑖𝑛{𝑀𝑎𝑥{𝑞𝐷𝐴𝑢𝑜𝛾 (𝑡), 𝑞𝐵𝑂𝐿𝑅𝑢𝑖𝛾 (𝑡)}, 𝑞𝐵𝑂𝐿𝑅𝑢(𝑖+1)𝛾 (𝑡)}
− 𝑀𝑖𝑛{𝑀𝑎𝑥{𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡), 𝑞𝐵𝑂𝐿𝑅𝑢𝑖𝛾 (𝑡)}, 𝑞𝐵𝑂𝐿𝑅𝑢(𝑖+1)𝛾 (𝑡)}
A.8.1.2
When calculating the value for the qBOACURLuoiγ(t) for the Decs resulting
from the Bid Offer Acceptance, the Market Operator shall calculate the
relevant variables as follows:
53
𝑞𝐷𝐴𝑢𝑜𝛾 (𝑡) = 𝑞𝐷𝐴𝐶𝑈𝑅𝐿𝑢𝑜𝛾 (𝑡)
𝐼𝑓 𝐷𝐼 𝑓𝑜𝑟 𝑜 ℎ𝑎𝑠 𝑐𝑢𝑟𝑡𝑎𝑖𝑙𝑚𝑒𝑛𝑡 𝑓𝑙𝑎𝑔, 𝑡ℎ𝑒𝑛
𝑞𝐷𝐴𝐶𝑈𝑅𝐿𝑢𝑜𝛾 (𝑡) = 𝑀𝑖𝑛 (𝑞𝐷𝑢𝑜𝛾 (𝑡), 𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡))
𝑒𝑙𝑠𝑒
𝑞𝐷𝐴𝐶𝑈𝑅𝐿𝑢𝑜𝛾 (𝑡) = 𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡)
𝑞𝐷𝐴𝑢(𝑜−1)𝛾 (𝑡) = 𝑞𝐷𝑢(𝑜−1)𝛾 (𝑡)
𝑞𝐷𝑢(𝑜=0)𝛾 (𝑡) = 𝑀𝑖𝑛 (𝑞𝐹𝑃𝑁𝑢𝛾 (𝑡), 𝑞𝐴𝑉𝐴𝐼𝐿𝑂𝑢𝛾 (𝑡))
𝑞𝐵𝑂𝑈𝑅𝑢(𝑖=0)𝛾 (𝑡) = 0
𝑞𝐵𝑂𝐿𝑅𝑢(𝑖=0)𝛾 (𝑡) = 0
where:
A.8.1.3
(a)
qDuoγ(t) is the Dispatch Quantity as a function of time for Generator
Unit, u, for Bid Offer Acceptance, o, in Imbalance Settlement Period,
γ;
(b)
qDAuoγ(t) is the Adjusted Dispatch Quantity as a function of time for
Generator Unit, u, for Bid Offer Acceptance, o, in Imbalance
Settlement Period, γ;
(c)
QDACURLuoγ(t) is the Curtailment Adjusted Dispatch Quantity as a
function of time for Generator Unit, u, for Bid Offer Acceptance, o, in
Imbalance Settlement Period, γ;
(d)
qBOURuiγ(t) is the Bid Offer Upper Range Quantity as a function of
time for Generator Unit, u, for Band, i, in Imbalance Settlement
Period, γ;
(e)
qBOLRuiγ(t) is the Bid Offer Lower Range Quantity as a function of
time for Generator Unit, u, for Band, i, in Imbalance Settlement
Period, γ;
(f)
qFPNuγ(t) is the Final Physical Notification Quantity as a function of
time for Generator Unit, u, in Imbalance Settlement Period, γ;
(g)
qAVAILOuγ(t) is the Outturn Availability Quantity as a function of time
for Generator Unit, u, in Imbalance Settlement Period, γ;
(h)
(o – 1) is for the previous Bid Offer Acceptance.
(i)
(i – 1) is for the previous Band when considering Bands in the positive
direction (i > 0);
(j)
(i + 1) is for the previous Band when considering Bands in the
negative direction (i < 0);
(k)
(o = 0) or (i = 0) is for the 0th value for the relevant aspect (i.e. the
implicit default value before an explicit Bid Offer Acceptance, o; the
value for Band, i, where i = 0).
The Market Operator shall calculate the Curtailment Accepted Bid Quantity
(qABCURLuoiγ(t)) as a function of time, for each Generator Unit, u, for each
Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ,
as follows:
54
𝑞𝐴𝐵𝐶𝑈𝑅𝐿𝑢𝑜𝑖𝛾 (𝑡) = 𝑀𝑖𝑛(𝑞𝐵𝑂𝐴𝐶𝑈𝑅𝐿𝑢𝑜𝑖𝛾 (𝑡) 𝑓𝑜𝑟 𝐷𝑒𝑐𝑠, 0)
where:
(a)
qBOACURLuoiγ(t) is the Curtailment Accepted Bid Offer Quantity as a
function of time for Generator Unit, u, for Bid Offer Acceptance, o, for
Band, i, in Imbalance Settlement Period, γ.
A.8.1.4
The Market Operator shall calculate the Curtailment Accepted Bid Quantity
(QABCURLuoiγ) as an integrated quantity for the Imbalance Settlement Period
γ, by integrating the associated function of time version of the Curtailment
Accepted Bid Quantity (qABCURLuoiγ(t)) with respect to time across the
Imbalance Settlement Period, γ.
A.8.2
Calculation of Curtailment Prices
A.8.2.1
The Market Operator shall calculate the Curtailment Price (PCURLγ) in
Imbalance Settlement Period, γ, in accordance with the curtailment price
process in section [on ex-ante market reference prices].
A.8.3
Calculation of Curtailment Charges
Explanatory Note
The intention of the equation below is as follows:
A.8.3.1
-
Implicitly remove the curtailed quantity from the imbalance component (by
applying “-PIMB” to it), and apply the curtailment price to the delivered,
unbiased quantities (PCURL). Since the quantity has been removed from the
premium/discount component, this is now the only price applied to this volume.
-
The undelivered quantity is removed to only remunerate delivered quantities,
and the biased quantity is removed to only remunerate those curtailment decs
which mean the volume of output of the unit is less than the ex-ante market
position of the unit: the biased quantities are decs above the ex-ante market
position.
The Market Operator shall calculate the Curtailment Charge (CCURLuγ) for
each Generator Unit, u, in each Imbalance Settlement Period, γ, as follows:
𝐶𝐶𝑈𝑅𝐿𝑢𝛾 = ∑ ∑ ((𝑃𝐶𝑈𝑅𝐿𝛾 − 𝑃𝐼𝑀𝐵𝛾 )
𝑜
𝑖
× (𝑄𝐴𝐵𝐶𝑈𝑅𝐿𝐿𝐹𝑢𝑜𝑖𝛾 − 𝑀𝑖𝑛(𝑄𝐴𝐵𝐵𝐼𝐴𝑆𝑢𝑜𝑖𝛾 , 𝑄𝐴𝐵𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾 )))
where:
(a)
PIMBγ is the Imbalance Settlement Price in Imbalance Settlement
Period, γ[, as calculated in section on Imbalance Pricing];
(b)
PCURLγ is the Curtailment Price in Imbalance Settlement Period, γ;
(c)
QABCURLLFuoiγ is the Loss-Adjusted Curtailment Accepted Bid
Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band,
i, in Imbalance Settlement Period, γ;
(d)
QABUNDELuoiγ is the Undelivered Accepted Bid Quantity for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in
Imbalance Settlement Period, γ;
55
(e)
A.8.3.2
A.9
QABBIASuoiγ is the Biased Accepted Bid Quantity for Generator Unit,
u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement
Period, γ.
The provisions in section A.8 do not apply to any unit which is:
(a)
An Assetless Unit;
(b)
A Trading Unit;
(c)
An Interconnector Error Unit;
(d)
An Autonomous Generator Unit.
UNINSTRUCTED IMBALANCE QUANTITIES AND CHARGES
Explanatory notes
-
Calculate the values for the tolerances allowed for uninstructed imbalances (over
generation and under generation).
-
Calculate the uninstructed imbalance volume on a unit for a period (different than the
imbalance component which includes instructed imbalances, this is the difference
between what the unit was instructed to do, and what they delivered), and the volume
thereof which is outside of the allowed tolerance.
-
Determine, from the orders accepted and the uninstructed imbalance volume on the
unit, the volume of the orders, in whole or a fraction, which were not delivered and
outside of the allowed tolerance (i.e. for over-delivery, decs deemed not to have been
delivered, for under-delivery, incs deemed not to have been delivered).
-
Calculate the additional charge to be applied to the uninstructed imbalance volume
outside of tolerance at the imbalance Settlement price (imbalance component of the
uninstructed imbalance charge).
-
Calculate the additional charge to be applied to the premium or discount for the
undelivered volumes which were deemed to be outside the allowed tolerance.
A.9.1
Setting of Uninstructed Imbalance Parameters
A.9.1.1
If requested by the Regulatory Authorities, the System Operators shall report
to the Regulatory Authorities [at least four months before the start of the
Year], proposing values for the following parameters to be used in the
calculation of Uninstructed Imbalances for that Year:
A.9.1.2
(a)
The Engineering Tolerance (TOLENG) (where 0  TOLENG  1);
(b)
The MW Tolerance (TOLMW t) (where 0  TOLMWt) for each Trading
Day, t;
(c)
The System per Unit Regulation Factor (FUREG);
(d)
The Discount for Over Generation Factor (FDOGuγ) for each
Generator Unit, u, in each Imbalance Settlement Period, γ, such that
0  FDOGuγ  1; and
(e)
The Premium for Under Generation Factor (FPUGuγ) for each
Generator Unit, u, in each Imbalance Settlement Period, γ, such that
0  FPUGuγ  1.
The System Operators’ report must set out any relevant research or analysis
carried out by the System Operators and any justification for the specific
values proposed. The report may, and shall if so requested by the
Regulatory Authorities, include alternative values from those proposed and
must set out the arguments for and against such alternatives.
56
A.9.1.3
The System Operators shall[, in accordance with Appendix K “Market Data
Transactions”,] provide to the Market Operator at least [two months] prior to
the start of each Year or within [5 Working Days] of approval by the
Regulatory Authorities, whichever is the later, the Uninstructed Imbalance
Parameters Data Transaction, which comprises a complete set of
Uninstructed Imbalance Parameters that have been approved by the
Regulatory Authorities for that Year.
A.9.1.4
The Market Operator shall publish the approved value(s) for each
Uninstructed Imbalance Parameter within [5 Working Days] of receipt of the
Regulatory Authorities' determination or [two months] before the start of the
Year to which they shall apply whichever is the later.
A.9.2
Calculation of Uninstructed Imbalance Tolerance Quantities
A.9.2.1
For each Trading Day, each System Operator shall submit to the Market
Operator the System Characteristics Data, consisting of values of Nominal
System Frequency (FRQNORγ) and Average System Frequency (FRQAVGγ)
for each Imbalance Settlement Period, γ, in that Trading Day, Market
Operator[, in accordance with Appendix K “Market Data Transactions”].
A.9.2.2
The Market Operator shall calculate the Tolerance Bands for over generation
and under generation for each Generator Unit for each Trading Period with
reference to system frequency and the frequency characteristics of the
Generator Unit in accordance with paragraphs A.9.2.3 and A.9.2.4.
A.9.2.3
The Market Operator shall calculate the Engineering Limit Quantity
(qLIMENGuγ) for each Generator Unit, u, in each Imbalance Settlement
Period, γ, as follows:
𝑞𝐿𝐼𝑀𝐸𝑁𝐺𝑢𝛾 = 𝑀𝑎𝑥 (|
𝑄𝐷𝑢𝛾
| × 𝑇𝑂𝐿𝐸𝑁𝐺, 𝑇𝑂𝐿𝑀𝑊𝑡 )
𝐷𝐼𝑆𝑃
where:
A.9.2.4
(a)
QDuγ is the Dispatch Quantity for Generator Unit, u, in Imbalance
Settlement Period, γ;
(b)
TOLENG is the Engineering Tolerance;
(c)
DISP is the Imbalance Settlement Period Duration; and
(d)
TOLMW t is the MW Tolerance for the relevant Imbalance Settlement
Period, γ, within Trading Day, t.
The Market Operator shall calculate the Tolerance for Over Generation
(TOLOGuγ) and Tolerance for Under Generation (TOLUGuγ) as positive
values, expressed in MW, for each Generator Unit, u, in each Imbalance
Settlement Period, γ, as follows:
𝐼𝑓 𝐹𝑅𝑄𝐴𝑉𝐺𝛾 ≤ 𝐹𝑅𝑄𝑁𝑂𝑅𝛾 , 𝑡ℎ𝑒𝑛
(𝐹𝑅𝑄𝑁𝑂𝑅𝛾 − 𝐹𝑅𝑄𝐴𝑉𝐺𝛾 ) × 𝑞𝐶𝑅𝑢
𝑇𝑂𝐿𝑂𝐺𝑢𝛾 = (
) + 𝑞𝐿𝐼𝑀𝐸𝑁𝐺𝑢𝛾
𝐹𝑈𝑅𝐸𝐺 × 𝐹𝑅𝑄𝑁𝑂𝑅𝛾
𝑇𝑂𝐿𝑈𝐺𝑢𝛾 = 𝑞𝐿𝐼𝑀𝐸𝑁𝐺𝑢𝛾
𝑒𝑙𝑠𝑒
𝑇𝑂𝐿𝑂𝐺𝑢𝛾 = 𝑞𝐿𝐼𝑀𝐸𝑁𝐺𝑢𝛾
57
𝑇𝑂𝐿𝑈𝐺𝑢𝛾 = (
(𝐹𝑅𝑄𝐴𝑉𝐺𝛾 − 𝐹𝑅𝑄𝑁𝑂𝑅𝛾 ) × 𝑞𝐶𝑅𝑢
) + 𝑞𝐿𝐼𝑀𝐸𝑁𝐺𝑢𝛾
𝐹𝑈𝑅𝐸𝐺 × 𝐹𝑅𝑄𝑁𝑂𝑅𝛾
where:
(a)
FRQAVGγ is the Average System Frequency in Imbalance Settlement
Period, γ;
(b)
FRQNORγ is the Nominal System Frequency in Imbalance Settlement
Period, γ;
(c)
qCRu is the Registered Capacity of Generator Unit, u;
(d)
FUREG is the System per Unit Regulation parameter; and
(e)
qLIMENGuγ is the Engineering Limit Quantity for Generator Unit, u, in
Imbalance Settlement Period, γ.
A.9.2.5
The provisions of section A.9.2 do not apply to any unit which isan
Interconnector Error Unit.
A.9.3
Calculation of Uninstructed Imbalance Quantities
A.9.3.1
The Market Operator shall calculate the Outside Tolerance Undelivered
Quantity (QUNDELOTOLuγ) for each Generator Unit, u, in Imbalance
Settlement Period, γ, as follows:
𝐼𝑓 (𝑄𝑀𝐿𝐹𝑢𝛾 − 𝑄𝐷𝐿𝐹𝑢𝛾 ) < 0, 𝑡ℎ𝑒𝑛
𝑄𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝛾 = 𝑀𝑖𝑛 ((𝑄𝑀𝐿𝐹𝑢𝛾 − 𝑄𝐷𝐿𝐹𝑢𝛾 ) + 𝑇𝑂𝐿𝑈𝐺𝐿𝐹𝑢𝛾 , 0)
𝐼𝑓 (𝑄𝑀𝐿𝐹𝑢𝛾 − 𝑄𝐷𝐿𝐹𝑢𝛾 ) > 0, 𝑡ℎ𝑒𝑛
𝑄𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝛾 = 𝑀𝑎𝑥 ((𝑄𝑀𝐿𝐹𝑢𝛾 − 𝑄𝐷𝐿𝐹𝑢𝛾 ) − 𝑇𝑂𝐿𝑂𝐺𝐿𝐹𝑢𝛾 , 0)
where:
(a)
QMLFuγ is the Loss-Adjusted Metered Quantity for Generator Unit, u,
in Imbalance Settlement Period, γ;
(b)
QDLFuγ is the Loss-Adjusted Dispatch Quantity for Generator unit, u,
in Imbalance Settlement Period, γ;
(c)
TOLUGLFuγ is the Loss-Adjusted Tolerance for Under Generation for
Generator Unit, u, in Imbalance Settlement Period, γ; and
(d)
TOLOGLFuγ is the Loss-Adjusted Tolerance for Over Generation for
Generator Unit, u, in Imbalance Settlement Period, γ.
A.9.3.2
Where the Outside Tolerance Undelivered Quantity has a positive value, the
Market Operator shall determine which of the Undelivered Accepted Bid
Quantities were outside of tolerance, in whole or in part, for each Generator
Unit, u, in Imbalance Settlement Period, γ, in accordance with paragraphs
A.9.3.3 to A.9.3.6.
A.9.3.3
The Market Operator shall derive a ranked set of all Undelivered Accepted
Bid Quantities for Generator Unit, u, in Imbalance Settlement Period, γ, in
order of increasing price. The Undelivered Accepted Bid Quantity with the
lowest price will be allocated a rank number n = 1, the next lowest priced
Undelivered Accepted Bid Quantity a rank number n = 2 and so on until all
58
Undelivered Accepted Bid Quantities have been allocated a rank number.
Where two or more Undelivered Accepted Bid Quantities have equal prices,
they shall be ranked using a systematic process of random selection which
may include making small alterations to the submitted prices. Any such
amended prices will only be used for this purpose in the ranking process.
Explanatory Note
The intention of the equations in sections A.9.3.4 to A.9.3.15 below is as follows:
-
A.9.3.4
This is the same as the function for determining which quantities are undelivered
used in Section A.6.6, but with different inputs. Now we only want to see which of
the undelivered quantities were outside of tolerance
The Market Operator shall calculate the Outside Tolerance Undelivered
Accepted Bid Quantity (QABUNDELOTOLuoiγn) for each Generator Unit, u, for
each Bid Offer Acceptance, o, for each Band, i, in ascending order of each
position, n, in the ranked set, in Imbalance Settlement Period, γ, as follows:
𝑄𝐴𝐵𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝑜𝑖𝛾𝑛
= 𝑀𝑖𝑛(𝑀𝑎𝑥(𝑄𝐴𝐵𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾𝑛 , −𝑄𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑅𝑢𝛾(𝑛−1) ), 0)
𝑄𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑅𝑢𝛾𝑛 = 𝑄𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑅𝑢𝛾(𝑛−1) + 𝑄𝐴𝐵𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝑜𝑖𝛾𝑛
𝑄𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑅𝑢𝛾(𝑛=0) = 𝑄𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝛾
This is done in ascending order of each position, n, in the ranked set.
where:
A.9.3.5
(a)
QABUNDELuoiγn is the Undelivered Accepted Bid Quantity for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in the
ranked set at rank, n, in Imbalance Settlement Period, γ;
(b)
QUNDELOTOLRuγn is the Remaining Outside Tolerance Undelivered
Quantity for Generator Unit, u, for the calculations in the ranked set at
rank, n, in Imbalance Settlement Period, γ;
(c)
QUNDELOTOLuγ is the Outside Tolerance Undelivered Quantity for
Generator Unit, u, in Imbalance Settlement Period, γ;
(d)
(n – 1) is for the previous item in the ranked set; and
(e)
(n = 0) is for the 0th item in the ranked set, i.e. where a calculation is
being performed on the first item in the ranked set, (n = 1), for which
there is no previous item.
The Market Operator shall calculate the Outside Tolerance Undelivered
Accepted Bid Quantity (QABUNDELOTOLuoiγ) for each Generator Unit, u, for
each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement
Period, γ, as follows:
𝑄𝐴𝐵𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝑜𝑖𝛾 = 𝑄𝐴𝐵𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝑜𝑖𝛾𝑛
where:
59
(a)
A.9.3.6
QABUNDELOTOLuoiγn is the Outside Tolerance Undelivered Accepted
Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for
Band, i, for position in the rank set, n, in Imbalance Settlement
Period, γ.
The Market Operator shall determine the Outside Tolerance Undelivered
Accepted Offer Quantity (QAOUNDELOTOLuoiγ) for each Generator Unit, u,
for each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement
Period, γ, as follows:
𝑄𝐴𝑂𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝑜𝑖𝛾 = 0
A.9.3.7
Where the Outside Tolerance Undelivered Quantity has a negative value, the
Market Operator shall determine which of the Undelivered Accepted Offer
Quantities were outside of tolerance, in whole or in part, for each Generator
Unit, u, in Imbalance Settlement Period, γ, in accordance with paragraphs
A.9.3.8 to A.9.3.11.
A.9.3.8
The Market Operator shall derive a ranked set of all Undelivered Accepted
Offer Quantities for Generator Unit, u, in Imbalance Settlement Period, γ, in
order of decreasing price. The Undelivered Accepted Offer Quantity with the
highest price will be allocated a rank number n = 1, the next highest priced
Undelivered Accepted Offer Quantity a rank number n = 2 and so on until all
Undelivered Accepted Offer Quantities have been allocated a rank number.
Where two or more Undelivered Accepted Offer Quantities have equal
prices, they shall be ranked using a systematic process of random selection
which may include making small alterations to the submitted prices. Any
such amended prices will only be used for this purpose in the ranking
process.
A.9.3.9
The Market Operator shall calculate the Outside Tolerance Undelivered
Accepted Offer Quantity (QAOUNDELOTOLuoiγn) for each Generator Unit, u,
for each Bid Offer Acceptance, o, for each Band, i, in ascending order of
each position, n, in the ranked set, in Imbalance Settlement Period, γ, as
follows:
𝑄𝐴𝑂𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝑜𝑖𝛾𝑛
= 𝑀𝑎𝑥(𝑀𝑖𝑛(𝑄𝐴𝑂𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾𝑛 , −𝑄𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑅𝑢𝛾(𝑛−1) ), 0)
𝑄𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑅𝑢𝛾𝑛 = 𝑄𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑅𝑢𝛾(𝑛−1) + 𝑄𝐴𝑂𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝑜𝑖𝛾𝑛
𝑄𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑅𝑢𝛾(𝑛=0) = 𝑄𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝛾
This is done in ascending order of each position, n, in the ranked set.
where:
(a)
QAOUNDELuoiγn is the Undelivered Accepted Offer Quantity for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in the
ranked set at rank, n, in Imbalance Settlement Period, γ;
(b)
QUNDELOTOLRuγn is the Remaining Outside Tolerance Undelivered
Quantity for Generator Unit, u, for the calculations in the ranked set at
rank, n, in Imbalance Settlement Period, γ;
60
(c)
QUNDELOTOLuγ is the Outside Tolerance Undelivered Quantity for
Generator Unit, u, in Imbalance Settlement Period, γ;
(d)
(n – 1) is for the previous item in the ranked set; and
(e)
(n = 0) is for the 0th item in the ranked set, i.e. where a calculation is
being performed on the first item in the ranked set, (n = 1), for which
there is no previous item.
A.9.3.10 The Market Operator shall calculate the Outside Tolerance Undelivered
Accepted Offer Quantity (QAOUNDELOTOLuoiγ) for each Generator Unit, u,
for each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement
Period, γ, as follows:
𝑄𝐴𝑂𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝑜𝑖𝛾 = 𝑄𝐴𝑂𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝑜𝑖𝛾𝑛
where:
(a)
QAOUNDELOTOLuoiγn is the Outside Tolerance Undelivered
Accepted Offer Quantity for Generator Unit, u, for Bid Offer
Acceptance, o, for Band, i, for position in the rank set, n, in Imbalance
Settlement Period, γ.
A.9.3.11 The Market Operator shall determine Outside Tolerance Undelivered
Accepted Bid Quantity (QABUNDELOTOLuoiγn) for each Generator Unit, u, for
each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement
Period, γ, as follows:
𝑄𝐴𝐵𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝑜𝑖𝛾 = 0
A.9.3.12 Where the Outside Tolerance Undelivered Quantity has a zero value, the
Market Operator shall determine the Outside Tolerance Undelivered
Accepted Offer Quantity (QAOUNDELOTOLuoiγ) and Outside Tolerance
Undelivered Accepted Bid Quantity (QABUNDELOTOLuoiγn) for each
Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in
Imbalance Settlement Period, γ, as follows:
𝑄𝐴𝑂𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝑜𝑖𝛾 = 0
𝑄𝐴𝐵𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝑜𝑖𝛾 = 0
A.9.3.13 The price for each Outside Tolerance Undelivered Accepted Offer Quantity
and Outside Tolerance Undelivered Accepted Bid Quantity (PBOuβoiγ) shall
be the same as the price for the individual Accepted Bid Quantity and
Accepted Offer Quantity to which they are related through belonging to the
same Generator Unit, u, and Bid Offer Acceptance, o, and Band, i, and
Imbalance Settlement Period, γ.
A.9.3.14 The provisions of paragraphs A.9.3.1 to A.9.3.13 do not apply to any unit
which is an Interconnector Error Unit.
A.9.3.15 The Market Operator shall assign the Outside Tolerance Undelivered
Accepted Offer Quantities and Outside Tolerance Undelivered Accepted Bid
Quantities, QAOUNDELOTOLuoiγ and QABUNDELOTOLuoiγ, calculated in
accordance with paragraphs A.9.3.1 to A.9.3.13 for an Interconnector
61
Residual Capacity Unit, u, to the Interconnector Error Unit, u, relevant to the
same Interconnector, l, as the Interconnector Residual Capacity Unit, and
shall set the values of these quantities for the Interconnector Residual
Capacity Unit to zero, for the purposes of all following processes using these
quantities.
A.9.4
Calculation of Uninstructed Imbalance Charges
Explanatory Note
The intention of the equation below is as follows:
A.9.4.1
-
This is slightly different to the SEM. In the SEM, uninstructed imbalances outside of
tolerance are paid an adjusted price. In the I-SEM, all uninstructed imbalances are
paid the imbalance Settlement price through the imbalance component, and a
premium/discount if applicable. This section calculates the “adjustment” to the price,
in the form of an additional charge.
-
If the total undelivered outside of tolerance quantity is negative (undergeneration), the
PUG is applied. It is firstly applied to the imbalance Settlement price which was used
to settle all the volume, and then applied to the discount which was used to settle the
accepted bid quantities.
-
If the total undelivered outside of tolerance quantity is positive (overgeneration),
similarly a DOG is applied.
Subject to paragraph A.9.4.2, the Market Operator shall calculate the
Uninstructed Imbalance Charge (CUNIMBuγ) for each Generator Unit, u, in
each Imbalance Settlement Period, γ, as follows:
𝐶𝑈𝑁𝐼𝑀𝐵𝑢𝛾 = 𝑀𝑖𝑛(𝑄𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝛾 , 0) × ((𝐹𝑃𝑈𝐺𝑢𝛾 × 𝑃𝐼𝑀𝐵𝛾 ))
+ 𝑀𝑎𝑥(𝑄𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝛾 , 0) × (−(𝐹𝐷𝑂𝐺𝑢𝛾 × 𝑃𝐼𝑀𝐵𝛾 ))
+ ∑ ∑ −𝐹𝐷𝑂𝐺𝑢𝛾
𝑜
𝑖
× (𝑀𝑖𝑛(𝑃𝐵𝑂𝑢𝛽𝑜𝑖𝛾 − 𝑃𝐼𝑀𝐵𝛾 , 0) × (𝑄𝐴𝐵𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝑜𝑖𝛾 ))
+ ∑ ∑ −𝐹𝑃𝑈𝐺𝑢𝛾
𝑜
𝑖
× (𝑀𝑎𝑥(𝑃𝐵𝑂𝑢𝛽𝑜𝑖𝛾 − 𝑃𝐼𝑀𝐵𝛾 , 0) × (𝑄𝐴𝑂𝑈𝑁𝐷𝐸𝐿𝑂𝑇𝑂𝐿𝑢𝑜𝑖𝛾 ))
where:
(a)
QUNDELOTOLuγ is the Outside Tolerance Undelivered Quantity for
Generator Unit, u, in Imbalance Settlement Period, γ.
(b)
QAOUNDELOTOLuoiγn is the Outside Tolerance Undelivered
Accepted Offer Quantity for Generator Unit, u, for Bid Offer
Acceptance, o, for Band, i, in Imbalance Settlement Period, γ.
(c)
QABUNDELOTOLuoiγn is the Outside Tolerance Undelivered Accepted
Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for
Band, i, in Imbalance Settlement Period, γ.
(d)
PIMBγ is the Imbalance Settlement Price in Imbalance Settlement
Period, γ[, as calculated in section on Imbalance Pricing];
(e)
PBOuβoiγ is the Bid Offer Price for each individual Outside Tolerance
Undelivered Accepted Bid Quantity and Outside Tolerance Accepted
Offer Quantity for Generator Unit, u, time stamped, β, as the last one
62
submitted by the relevant Participant before Bid Offer Acceptance, o,
for Band, i, in Imbalance Settlement Period, γ;
(f)
FPUGuγ is the Premium for Under Generation Factor for Generator
Unit, u, in Imbalance Settlement Period, γ.
(g)
FDOGuγ is the Discount for Over Generation Factor for Generator
Unit, u, in Imbalance Settlement Period, γ.
A.9.4.2
When a Pumped Storage Unit, u, is in Pumping Mode for an Imbalance
Settlement Period, γ, or any part thereof, the Market Operator shall calculate
the Imbalance Component Payment or Charge (CUNIMBuγ) for that Pumped
Storage Unit, u, in each Imbalance Settlement Period, γ, for which it is in
Pumping Mode, as having a value of zero.
A.9.4.3
The provisions of section A.9 do not apply to any unit which is:
A.10
(a)
An Assetless Unit;
(b)
A Trading Unit;
(c)
An Autonomous Generator Unit;
(d)
An Interconnector Residual Capacity Unit;
(e)
An Autonomous Generator Unit .
INFORMATION IMBALANCE QUANTITIES AND CHARGES
Explanatory notes
A.10.1
-
Calculate the information imbalance volume for a given period by calculating
volumes, for all times where a PN submission relevant to that period can be made, of
the differences between the submitted PN values for that period and the FPN
submission for that period, and applying a weighting factor to each of those volumes
to determine if that volume (or how much of that volume) makes up the total
information imbalance volume.
-
Determine the information imbalance charge to be applied in a particular period
through the application of the information imbalance price to the calculated quantity.
Setting of Information Imbalance Parameters
A.10.1.1 If requested by the Regulatory Authorities, the [Market Operator] shall report
to the Regulatory Authorities at least [4 months] before the start of the Year,
proposing values for the following parameters to be used in the calculation of
Information Imbalance Charges for that Year:
(a)
The Information Imbalance Quantity Weighting Factor (WFQII uβγ) for
each Generator Unit, u, for each PN Submission Period, β, in respect
of Imbalance Settlement Period, γ, for Year, y;
(b)
The Information Imbalance Tolerance (TOLIIuβγ) for each Generator
Unit, u, for each PN Submission Period, β, in respect of Imbalance
Settlement Period, γ, for Year, y; and
(c)
The Information Imbalance Price (PIIuγ) for each Generator Unit, u, in
each Imbalance Settlement Period, γ.
A.10.1.2 The [Market Operator's] report must set out any relevant research or analysis
carried out by the Market Operator and the justification or sources for the
specific values proposed. The report may, and shall if so requested by the
Regulatory Authorities, include alternative values from those proposed and
must set out the arguments for and against such alternatives.
63
A.10.1.3 The [Market Operator] shall publish the approved value(s) for each such
parameter within [5 Working Days] of receipt of the Regulatory Authorities'
determination or [two months] before the start of the year to which they shall
apply, whichever is the later.
A.10.2
Calculation of Information Imbalance Quantities
Explanatory Note
The intention of the equation below is as follows:
-
Determine the information imbalance quantity, which is the difference between the
PN for period gamma at a certain submission time beta, and the FPN for gamma after
all submission times for gamma have been finished. If this quantity is outside of a
tolerance, it is considered. A weighting factor is then applied to only consider the
quantities outside of tolerance arising in submission times we care about, e.g. we
might not care if QPN is very different to QFPN at the start of the trading day, but if
QPN is very different to QFPN 2 hours before real-time it could be deemed
important].
A.10.2.1 The Market Operator shall calculate the Information Imbalance Quantity
(QIIuγ) for each Generator Unit, u, in each Imbalance Settlement Period, γ, as
follows:
𝑄𝐼𝐼𝑢𝛾 =
∑
𝑀𝑎𝑥(|𝑄𝑃𝑁𝑢𝛽𝛾 − 𝑄𝐹𝑃𝑁𝑢𝛾 | − 𝑇𝑂𝐿𝐼𝐼𝑢𝛽𝛾 , 0) × 𝑊𝐹𝑄𝐼𝐼𝑢𝛽𝛾
𝛽 𝑟𝑒𝑙𝑒𝑣𝑎𝑛𝑡 𝑡𝑜 𝛾
where:
A.10.3
(a)
QPNuβγ is the last valid Physical Notification Quantity for Generator
Unit, u, in PN Submission Period, β, in respect of Imbalance
Settlement Period, γ.
(b)
∑𝛽 𝑟𝑒𝑙𝑒𝑣𝑎𝑛𝑡 𝑡𝑜 𝛾 is the sum, for each PN Submission Period β, in
respect of Imbalance Settlement Period γ.
(c)
QFPNuγ is the Final Physical Notification Quantity for Generator Unit,
u, in Imbalance Settlement Period, γ;
(d)
WFQIIuβγ is the Information Imbalance Quantity Weighting Factor for
Generator Unit, u, for PN Submission Period , β, in respect of
Imbalance Settlement Period, γ; and
(e)
TOLIIuβγ is the Information Imbalance Tolerance for Generator Unit, u,
for PN Submission Period, β, in respect of Imbalance Settlement
Period, γ.
Calculation of Information Imbalance Charges
A.10.3.1 The Market Operator shall calculate the Information Imbalance Charge (CIIuγ)
for each Generator Unit, u, in each Imbalance Settlement Period, γ, as
follows:
𝐶𝐼𝐼𝑢𝛾 = 𝑃𝐼𝐼𝑢𝛾 × 𝑄𝐼𝐼𝐿𝐹𝑢𝛾
where:
(a)
QIILFuγ is the Loss-Adjusted Information Imbalance Quantity for
Generator Unit, u, in Imbalance Settlement Period, γ;
64
(b)
PIIuγ is the Information Imbalance Price for Generator Unit, u, in
Imbalance Settlement Period, γ.
A.10.3.2 The provisions in section A.10 do not apply to any unit which is:
A.11
(a)
An Assetless Unit;
(b)
A Trading Unit;
(c)
An Interconnector Error Unit;
(d)
An Interconnector Residual Capacity Unit;
(e)
A unit which has Priority Dispatch, which is non-dispatchable;
(f)
An Autonomous Generator Unit.
FIXED COST PAYMENTS AND CHARGES
Explanatory notes:
-
Determine when a balancing market action results in the need to recover explicit start
costs and no-load costs from three-part order formats as part of imbalance
settlement.
-
If three-part order formats required to be used, ensure that the following requirements
are implemented in the functionality:
o
Non-energy actions to have their fixed costs remunerated through sidepayments;
o
Energy actions can have their fixed costs reflected in, and remunerated
through, the imbalance settlement price;
o
Ensuring that generators do not over-recover start costs over a contiguous
period;
o
Functionality for Substitutive PNs, where the IDM price achieved replaces
the price of the relevant balancing market order in full.
-
Where explicit fixed costs need to be paid to a generator unit, do this through a makewhole payment where the running costs for a unit due to balancing market actions
over a contiguous operating period and the revenue earned in the balancing market
by that unit over the period are compared, with any costs not recovered being
remunerated through an additional side-payment.
-
Adjustments to the approach for the make-whole payment were made to capture the
following case:
o
-
-
When a unit has been started, shut-down, and started again all within a
length of time with non-zero PN submitted, the previous approach would not
have recognised this as an additional start-up cost. This approach was
changed by ensuring that a start cost is recognised for every period of
physical running which has no PN associated, and every new start after a
shutdown within a length of time which has a PN associated.
Additional functionality has been added to this to account for situations where fixed
costs are recovered through a participant’s Complex COD rather than through their
Simple Dec price. This is to fully enact the Building Blocks decision, which states:
o
A unit that obtains an ex-ante market position or that is dispatched up will
receive at least its offer price; and
o
A unit that is constrained down from its ex-ante market position (and which
has firm access) will retain its inframarginal rent.
The second bullet point from the decision means that a unit would pay back their
avoided fixed costs where applicable when constrained down, as avoided costs taken
away from market revenue would leave inframarginal rent. A participant who has
avoided a start/no-load can pay this back through their Dec price if the Simple Data
applies, but there has not yet been provisions added for the functionality of paying
avoided fixed costs when Complex COD applies. Changes to the following section
65
reflect this additional required functionality:
A.11.1
o
Start costs are considered recoverable if there is no dispatch over the Period
of Market Operation (pure decommitment), and Complex COD applies;
o
Start costs are also considered recoverable if the start of the Period of
Market Operation, and the end of the previous Period of Market Operation,
are in the same Period of Physical Operation. This captures situations where
the TSO keeps a unit on when the unit was intending through its market
position to shut down and start up again, i.e. the unit pays back the avoided
start cost from the TSO keeping it on (again, if Complex COD applies);
o
No-Load costs are considered recoverable if there is no dispatch quantity in
an Imbalance Settlement Period within the Period of Market Operation (i.e.
there is a FPN, but no dispatch), and Complex COD applies.
Determination of Periods of Physical Operation and Market Operation
A.11.1.1 The Market Operator shall determine the start and end of each Period of
Physical Operation for each Generator Unit, u, in each Billing Period, b, as
follows:
(a)
(b)
A Period of Physical Operation will start at:
(i)
The time where the value for the final Dispatch Quantity
(qDuoγ(t)) of the Generator Unit, u, rises from zero; or
(ii)
The start of a Billing Period, if the value for the final Dispatch
Quantity (qDuoγ(t)) of the Generator Unit, u, was a positive
number at the end of the immediately preceding Billing Period;
A Period of Physical Operation will end at the earlier of:
(i)
The time where the value for the final Dispatch Quantity
(qDuoγ(t)) of the Generator Unit, u, becomes zero after
previously being a positive number greater than zero; and
(ii)
The end of a Billing Period.
A.11.1.2 The Market Operator shall determine the start and end of each Period of
Market Operation for each Generator Unit, u, in each Billing Period, b, as
follows:
(a)
(b)
A Period of Market Operation will start at:
(i)
The time where the value for the Final Physical Notification
Quantity (qFPNuγ(t)) of the Generator Unit, u, rises from zero;
or
(ii)
The start of a Billing Period, if the value for the Final Physical
Notification Quantity (qFPNuγ(t)) of the Generator Unit, u, was
a positive number at the end of the immediately preceding
Billing Period;
A Period of Market Operation will end at the earlier of:
(i)
The time where the value for the Final Physical Notification
(qFPNuγ(t)) of the Generator Unit, u, becomes zero after
previously being a positive number greater than zero; and
(ii)
The end of a Billing Period.
66
A.11.2
Determination of No-Load Costs and Start-Up Costs Payable and
Recoverable
A.11.2.1 In each of the following circumstances the Start-Up Costs (CSUuγ) payable
for each Generator Unit, u, in each Imbalance Settlement Period, γ, shall
have a value of zero for each Imbalance Settlement Period, γ, falling wholly
within the Period of Physical Operation, or in which the Period of Physical
Operation starts or ends, as follows:
(a)
When all Accepted Offer Quantities and Accepted Bid Quantities
within the Period of Physical Operation are priced on the basis of the
Simple Bid Offer Format Data as determined in section A.3.2;
(b)
When the Metered Quantity (QMuγ) for the Generator Unit, u, has a
value of zero for all Imbalance Settlement Periods, γ, falling wholly
within the Period of Physical Operation, or in which the Period of
Physical Operation starts or ends.
A.11.2.2 In all circumstances not listed in paragraphs A.11.2.1, for any Bid Offer
Acceptance, o, within the Period of Physical Operation which is associated
with a Synchronise Dispatch Instruction and for which Complex Bid Offer
Format data is to be used in accordance with section A.3.2:
(a)
(b)
CSUuγ for the first Imbalance Settlement Period, γ, within the Period
of Physical Operation shall have a value equal to the value of the
[Submitted Start Cost] relating to the Warmth State at the time of the
start time of the Period of Physical Operation submitted for the
Generator Unit as part of the applicable Complex Bid Offer Format if:
(i)
The Final Physical Notification Quantity (qFPNuγ(t)) for the
Generator Unit, u, has a value of zero for all times within the
Period of Physical Operation; or
(ii)
The start of the Period of Physical Operation and the end of
the previous Period of Physical Operation are within the same
Period of Market Operation;
(iii)
Otherwise, CSUuγ for the first Imbalance Settlement Period, γ,
within the Period of Physical Operation shall have a value of
zero.
CSUuγ shall have a value of zero for each other Imbalance Settlement
Period, γ, falling wholly within the Period of Physical Operation, or in
which the Period of Physical Operation starts or ends,
A.11.2.3 The Market Operator shall determine all No-Load Costs (CNLuγ) payable for
each Generator Unit, u, in each Imbalance Settlement Period, γ, as follows:
(a)
(b)
CNLuγ shall have a value of zero for each Imbalance Settlement
Period, γ, falling wholly within the Period of Physical Operation or in
which the Period of Physical Operation starts or ends, where:
(i)
The Final Physical Notification Quantity (qFPNuγ(t)) for the
Generator Unit, u, has a non-zero value for any time within
that Imbalance Settlement Period;
(ii)
The Metered Quantity (QMuγ) for the Generator Unit, u, has a
value of zero for that Imbalance Settlement Period, γ.
In all circumstances not listed in paragraph A.11.2.3(a):
(i)
Where, in accordance with section A.3.2, Complex Bid Offer
Format data is to be used in respect of the first Bid Offer
67
Acceptance, o, in an Imbalance Settlement Period, γ, falling
wholly within the Period of Physical Operation, or in which the
Period of Physical Operation starts or ends, CNLuγ shall have
a value equal to the [Submitted No-Load Cost] submitted for
the Generator Unit as part of that Complex Bid Offer Format,
multiplied by the Imbalance Settlement Period Duration
(DISP);
(ii)
Where, in accordance with section A.3.2, Simple Format data
is to be used in respect of the first Bid Offer Acceptance, o, in
an Imbalance Settlement Period, γ, falling wholly within the
Period of Physical Operation, or in which the Period of
Physical Operation starts or ends, CNLuγ shall have a value of
zero.
A.11.2.4 The Market Operator shall determine the Recoverable Start-Up Costs
(CSURuγ) for each Generator Unit, u, in each Imbalance Settlement Period,
γ, within the Period of Market Operation as follows:
(a)
(b)
CSURuγ for the first Imbalance Settlement Period, γ, within the Period
of Market Operation shall have a value equal to value of the
[Submitted Start Cost] relating to the Warmth State at the start time of
the Period of Physical Operation submitted for the Generator Unit as
part of the most recently submitted valid Complex Bid Offer Format
Data as at the Bid Offer Acceptance Time in respect of the first Bid
Offer Acceptance, o, for which Complex Bid Offer Format data is to
be used in accordance with section A.3.2, in that Imbalance
Settlement Period, γ, if:
(i)
The final Dispatch Quantity (qDuoγ(t)) for the Generator Unit, u,
has a value of zero for all times within the Period of Market
Operation; or
(ii)
The start of the Period of Market Operation and the end of the
previous Period of Market Operation are within the same
Period of Physical Operation;
(iii)
Otherwise, CSURuγ for the first Imbalance Settlement Period,
γ, within the Period of Market Operation shall have a value of
zero.
CSURuγ shall have a value of zero for each other Imbalance
Settlement Period, γ, falling wholly within the Period of Market
Operation, or in which the Period of Market Operation starts or ends.
A.11.2.5 The Market Operator shall determine all Recoverable No-Load Costs
(CNLRuγ) for each Generator Unit, u, in each Imbalance Settlement Period, γ,
as follows:
(a)
CNLRuγ shall have a value of zero for each Imbalance Settlement
Period, γ, falling wholly within the Period of Market Operation or in
which the Period of Market Operation starts or ends, where:
(i)
(b)
The Final Dispatch Quantity (qDuoγ(t)) for the Generator Unit,
u, has a non-zero value for any time within that Imbalance
Settlement Period.
In all circumstances not listed in paragraph A.11.2.5(a):
(i)
CNLRuγ shall have a value equal to the [Submitted No-Load
Cost] submitted for the Generator Unit as part of the most
68
recently submitted valid Complex Bid Offer Format Data as at
the Bid Offer Acceptance Time in respect of the first Bid Offer
Acceptance, o, in an Imbalance Settlement Period, γ, falling
wholly within the Period of Market Operation, or in which the
Period of Market Operation starts or ends, multiplied by the
Imbalance Settlement Period Duration (DISP);
(ii)
Where, in accordance with section A.3.2, Simple Format data
is to be used in respect of the first Bid Offer Acceptance, o, in
an Imbalance Settlement Period, γ, falling wholly within the
Period of Market Operation, or in which the Period of Market
Operation starts or ends, CNLRuγ shall have a value of zero.
A.11.2.6 For the purposes of calculations under this Code the Market Operator shall
calculate each value of Start-Up Costs (CSUuγ) for each Demand Side Unit,
u, from the relevant value of Shut Down Cost (CSDuγ) for the relevant
Imbalance Settlement Period, γ, for that Demand Side Unit. The Market
Operator shall set all values of No-Load Costs (CNLuγ) for Demand Side
Units u to be zero for all Imbalance Settlement Periods, γ.
A.11.3
Determination of Contiguous Operating Periods
A.11.3.1 The Market Operator shall determine the start and end of each Contiguous
Operating Period, k, for each Generator Unit, u, in each Billing Period, b, as
follows:
(a)
Subject to paragraph A.11.3.1(c), the start of a Contiguous Operating
Period, k, will be:
(b)
The start of the Imbalance Settlement Period, γ, during which
the value for the Dispatch Quantity (qDuγ) of the Generator
Unit, u, rises from zero;
(ii)
The start of the first Imbalance Settlement Period, γ, within a
Billing Period, if the value for the Dispatch Quantity (QDuγ) of
the Generator Unit, u, was greater than zero at the end of the
last Imbalance Settlement Period in the preceding Billing
Period.
Subject to paragraph A.11.3.1(c), the end of a Contiguous Operating
Period, k, will be the earlier of:
(c)
A.11.4
(i)
(i)
The end of the Imbalance Settlement Period, γ, during which
the value for the Dispatch Quantity (qDuγ) of the Generator
Unit, u, falls to zero; or
(ii)
The end of the last Imbalance Settlement Period, γ, within a
Billing Period.
A Contiguous Operating Period, k, shall not end where the value for
the Dispatch Quantity (qDuγ) of the Generator Unit, u, falls to zero but
then rises from zero within the same Imbalance Settlement Period,
but shall be treated as continuing during the period in which the value
is zero.
Calculation of Fixed Costs Payments and Charges
Explanatory Note
The intention of the equation below is as follows:
-
Calculate all the operational costs arising out of balancing market actions. This is the
69
sum of all no-load and start-up costs payable in the BM, as determined in the
previous section, and the cost of delivered accepted offers and accepted bids, as
determined by the price submitted by the participant for these offers and bids.
-
This is calculated for all periods in a contiguous operating period, then summed.
A.11.4.1 The Market Operator shall calculate the Make-Whole Payment Operating
Cost (COCMWPuk) for each Generator Unit, u, for each Contiguous
Operating Period, k, in each Billing Period, b, as follows:
𝐶𝑂𝐶𝑀𝑊𝑃𝑢𝑘 = ∑ (𝐶𝑁𝐿𝑢𝛾 + 𝐶𝑆𝑈𝑢𝛾
𝛾 𝑖𝑛 𝑘
+ ∑ ∑ (𝑃𝐵𝑂𝑢𝛽𝑜𝑖𝛾 × (𝑄𝐴𝑂𝐿𝐹𝑢𝑜𝑖𝛾 − 𝑄𝐴𝑂𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾 ))
𝑜
𝑖
+ ∑ ∑ (𝑃𝐵𝑂𝑢𝛽𝑜𝑖𝛾 × (𝑄𝐴𝐵𝐿𝐹𝑢𝑜𝑖𝛾 − 𝑄𝐴𝐵𝑈𝑁𝐷𝐸𝐿𝑢𝑜𝑖𝛾 )))
𝑜
𝑖
where:
(a)
CNLuγ is the No-Load Cost for Generator Unit, u, in Imbalance
Settlement Period, γ;
(b)
CSUuγ is the Start-Up Cost for Generator Unit, u, in Imbalance
Settlement Period, γ;
(c)
PBOuβoiγ is the Bid Offer Price for each individual Accepted Bid
Quantity and Accepted Offer Quantity for Generator Unit, u, time
stamped, β, as the last one submitted by the relevant Participant
before Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement
Period, γ;
(d)
QAOLFuoiγ is the Loss-Adjusted Accepted Offer Quantity for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in
Imbalance Settlement Period, γ;
(e)
QABLFuoiγ is the Loss-Adjusted Accepted Bid Quantity for Generator
Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance
Settlement Period, γ;
(f)
QAOUNDELuoiγ is the Undelivered Accepted Offer Quantity for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in
Imbalance Settlement Period, γ;
(g)
QABUNDELuoiγ is the Undelivered Accepted Bid Quantity for
Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in
Imbalance Settlement Period, γ.
Explanatory Note
The intention of the equation below is as follows:
-
Calculate all balancing market revenues relevant to a make-whole payment. This is
a sum of the cash flows calculated in previous sections, except for some additional
charges which should not be considered in a make-whole payment (i.e. to ensure
the unit isn’t made-whole for a charge which should stand to them.
A.11.4.2 The Market Operator shall calculate the Make-Whole Payment Revenue
(CREVMWPuk) for each Generator Unit, u, for each Contiguous Operating
Period, k, in each Billing Period, b, as follows:
70
𝐶𝑅𝐸𝑉𝑀𝑊𝑃𝑢𝑘 = ∑ (𝐶𝐼𝑀𝐵𝑢𝛾 + 𝐶𝑃𝑅𝐸𝑀𝐼𝑈𝑀𝑢𝛾 + 𝐶𝐷𝐼𝑆𝐶𝑂𝑈𝑁𝑇𝑢𝛾 + 𝐶𝐴𝑂𝑂𝑃𝑂𝑢𝛾
𝛾∈𝑘
+ 𝐶𝐴𝐵𝐵𝑃𝑂𝑢𝛾 + 𝐶𝐶𝑈𝑅𝐿𝑢𝛾 )
where:
(a)
CIMBuγ is the Imbalance Component Payment or Charge for
Generator Unit, u, in Imbalance Settlement Period, γ;
(b)
CPREMIUMuγ is the Premium Component Payment for Generator
Unit, u, in Imbalance Settlement Period, γ;
(c)
CDISCOUNTuγ is the Discount Component Payment for Generator
Unit, u, in Imbalance Settlement Period, γ;
(d)
CAOOPOuγ is the Offer Price Only Accepted Offer Payment or Offer
Price Only Accepted Offer Charge for Generator Unit, u, in Imbalance
Settlement Period, γ;
(e)
CABBPOuγ is the Bid Price Only Accepted Bid Payment or Bid Price
Only Accepted Bid Charge, γ; and
(f)
CCURLuγ is the Curtailment Charge for Generator Unit, u, in
Imbalance Settlement Period, γ.
Explanatory Note
The intention of the equation below is as follows:
-
If the revenues of the unit in the balancing market over a contiguous operating
period are insufficient to cover their costs (primarily considering their explicit no-load
and start-up costs which have not yet been considered in their revenues), the unit is
made-whole to the required amount through this cash flow. Otherwise the value for
this cash flow is zero.
A.11.4.3 The Market Operator shall calculate the Make-Whole Payment (CMWPuk) for
each Generator Unit, u, for each Contiguous Operating Period, k, in each
Billing Period, b, as follows:
𝐶𝑀𝑊𝑃𝑢𝑘 = 𝑀𝑎𝑥(𝐶𝑂𝐶𝑀𝑊𝑃𝑢𝑘 − 𝐶𝑅𝐸𝑉𝑀𝑊𝑃𝑢𝑘 , 0)
where:
(a)
COCMWPuk is the Make-Whole Payment Operating Cost for
Generator Unit, u, in Contiguous Operating Period, k; and
(b)
CREVMWPuk is the Make-Whole Payment Revenue for Generator
Unit, u, in Contiguous Operating Period, k.
A.11.4.4 The Market Operator shall calculate the Fixed Cost Payment or Charge
(CFCub) for each Generator Unit, u, in each Billing Period, b, as follows:
𝐶𝐹𝐶𝑢𝑏 = ∑ 𝐶𝑀𝑊𝑃𝑢𝑘 − ∑(𝐶𝑁𝐿𝑅𝑢𝛾 + 𝐶𝑆𝑈𝑅𝑢𝛾 )
𝑘 ∈𝑏
𝛾 ∈𝑏
where:
(a)
CMWPuk is the Make-Whole Payment for Generator Unit, u, in
Contiguous Operating Period, k;
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(b)
CNLRuγ is the Recoverable No-Load Cost for Generator Unit, u, in
Imbalance Settlement Period, γ; and
(c)
CSURuγ is the Recoverable Start-Up Cost for Generator Unit, u, in
Imbalance Settlement Period, γ.
A.11.4.5 The provisions in section A.11 do not apply to any unit which is:
(a)
An Assetless Unit;
(b)
A Trading Unit;
(c)
An Interconnector Error Unit;
(d)
An Interconnector Residual Capacity Unit;
(e)
A unit which has Priority Dispatch, which is non-dispatchable;
(f)
An Autonomous Generator Unit.
A.12
IMPERFECTIONS CHARGES
A.12.1
Setting of Imperfections Charges Parameters
A.12.1.1 The Market Operator shall report to the Regulatory Authorities at least [4
months] before the start of the Year, proposing values for the following
parameters to be used in the calculation of Imperfections Charges for that
Year:
(a)
The Imperfections Price (PIMPy) in €/MWh for Year, y; and
(b)
the Imperfections Charge Factor (FCIMPγ) for each Imbalance
Settlement Period, γ, in Year, y.
A.12.1.2 The Market Operator's report must set out any relevant research or analysis
carried out by the Market Operator and the justification for the specific values
proposed. The report may, and shall if so requested by the Regulatory
Authorities, include alternative values from those proposed and must set out
the arguments for and against such alternatives.
A.12.1.3 The Market Operator shall publish the approved value(s) for each such
parameter within [5 Working Days] of receipt of the Regulatory Authorities'
determination or [two months] before the start of the Year to which they shall
apply whichever is the later.
A.12.1.4 The Market Operator may, of its own accord or in response to a request from
the Regulatory Authorities, make additional interim reports to the Regulatory
Authorities during the Year, proposing revisions to the Imperfections Charge
Factor in the event that the values as originally proposed do not provide for
the adequate recovery of anticipated costs and such under recovery is such
that it is not appropriate to include as an adjustment in subsequent Years.
A.12.1.5 The Market Operator shall publish the approved revised Imperfections
Charge Factor, and the date and time on which it comes into effect, within [5
Working Days] of receipt of the Regulatory Authorities' determination.
A.12.2
Calculation of Imperfections Charges
A.12.2.1 The purpose of the Imperfections Charge is to recover the anticipated
Dispatch Balancing Costs (less Other System Charges), Make Whole
Payments, any net imbalance between Energy Payments and Energy
Charges and Capacity Payments and Capacity Charges over the Year, with
adjustments for previous Years as appropriate.
72
A.12.2.2 The Market Operator shall calculate the Imperfections Charge (CIMPvγ) for
each Supplier Unit, v, in each Imbalance Settlement Period, γ, as follows:
𝐶𝐼𝑀𝑃𝑣𝛾 = 𝑀𝑖𝑛(𝑄𝑀𝐿𝐹𝑣𝛾 , 0) × 𝑃𝐼𝑀𝑃𝑦 × 𝐹𝐶𝐼𝑀𝑃𝛾
where:
(a)
PIMPy is the Imperfections Price for Year, y;
(b)
QMLFvγ is the Loss-Adjusted Metered Quantity for Supplier Unit, v, in
Imbalance Settlement Period, γ; and
(c)
FCIMPγ is the Imperfections Charge Factor for Imbalance Settlement
Period, γ.
A.12.2.3 The provisions in section A.12 do not apply to any unit which is:
(a)
A.13
A Trading Site Supplier Unit.
TESTING CHARGES
Explanatory note:
-
A.13.1
The Granting of Testing Status is built into the rules through the Data Submission
section. Which tariffs are used for different cases is outside the scope of the market
rules, and depends on the tariff setting consultation referred to in the first section
here.
Setting Testing Tariffs
A.13.1.1 If requested by the Regulatory Authorities, the relevant System Operator
shall report to the Regulatory Authorities proposing values for the Testing
Tariffs at least [four months] before the start of the Year to which they shall
apply. The System Operator's report must set out the justification for the
specific values proposed. The report may, and shall if so requested by the
Regulatory Authorities, include alternative values from those proposed and
must set out the arguments for and against such alternatives.
A.13.1.2 Each System Operator shall provide to the [Market Operator] at least [two
months] prior to the start of each Year or [within 5 Working Days] of approval
of the Testing Tariffs by the Regulatory Authorities whichever is the later, the
Testing Tariff Data Transaction, which comprises a complete set of Testing
Tariffs that have been approved by the Regulatory Authorities for each
Generator Unit (other than Demand Side Units) that is registered within its
Jurisdiction, for each Trading Period in the Year, y[, in accordance with
Appendix K “Market Data Transactions”].
A.13.1.3 The [Market Operator] shall publish the approved value(s) for each
parameter within [5 Working Days] of receipt of the Regulatory Authorities'
determination or [two months] before the start of the Year to which they shall
apply whichever is the later.
A.13.1.4 The System Operator may update the Testing Tariffs within the Year to
which they apply subject to the prior approval of the Regulatory Authorities. If
the Testing Tariffs are so updated, the System Operator shall provide the
updated Testing Tariff Data Transaction to the [Market Operator] within [5
Working Days] of approval by the Regulatory Authorities.
73
A.13.1.5 The [Market Operator] shall publish each Year the schedule of Testing Tariffs
and the detailed tariff methodology and periodically in the event that the
Tariffs are updated within a Year.
A.13.2
Calculation of Testing Charges
A.13.2.1 The Market Operator shall calculate the Testing Charge (CTESTuγ) for each
Generator Unit, u, except for any Interconnector Error Unit, u, in each
Imbalance Settlement Period, γ, for which it is Under Test as follows:
𝐶𝑇𝐸𝑆𝑇𝑢𝛾 = − 𝑀𝑎𝑥(𝑄𝑀𝐿𝐹𝑢𝛾 , 0) × 𝑃𝑇𝐸𝑆𝑇𝑇𝐴𝑅𝐼𝐹𝐹𝑢𝛾
where:
(a)
QMLFuγ is the Loss-Adjusted Metered Quantity for Generator Unit, u,
Under Test in Imbalance Settlement Period, γ;
(b)
PTESTTARIFFuγ is the Testing Tariff Price for Generator Unit, u,
Under Test in Imbalance Settlement Period, γ, as set out in the
schedule of Testing Tariffs.
A.13.2.2 The Market Operator shall calculate the Testing Charge (CTESTuγ) for each
Interconnector Error Unit, u, in each Imbalance Settlement Period, γ, for
which it is Under Test as follows:
𝐼𝑓 𝑄𝑀𝐿𝐹𝑢𝛾 > 0 𝑡ℎ𝑒𝑛
𝐶𝑇𝐸𝑆𝑇𝑢𝛾 = − 𝑀𝑎𝑥(𝑄𝑀𝐿𝐹𝑢𝛾 , 0) × 𝑃𝑇𝐸𝑆𝑇𝑇𝐴𝑅𝐼𝐹𝐹𝑢𝛾
𝑒𝑙𝑠𝑒
𝐶𝑇𝐸𝑆𝑇𝑢𝛾 = 𝑄𝑀𝐿𝐹𝑢𝛾 × 𝑃𝑇𝐸𝑆𝑇𝑇𝐴𝑅𝐼𝐹𝐹𝑢𝛾
where:
(a)
QMLFuγ is the Loss-Adjusted Metered Quantity for Interconnector
Error Unit, u, Under Test in Imbalance Settlement Period, γ;
(b)
PTESTTARIFFuγ is the Testing Tariff Price for Generator Unit, u,
Under Test in Imbalance Settlement Period, γ, as set out in the
schedule of Testing Tariffs.
A.14
RESIDUAL ERROR VOLUME CHARGES
A.14.1
Purpose
A.14.1.1 The purpose of the Residual Error Volume Charge is to recover costs in
relation to the loss adjusted Residual Error Volume which is the residual
energy calculated when total Loss Adjusted Metered Demand is deducted
from total Loss Adjusted Metered Generation for each Jurisdiction. The
Residual Error Volume Price is intended to cover the anticipated net
imbalance over the Year, with adjustments for previous Years as
appropriate.
A.14.2
Setting Residual Error Volume Charges Parameters
A.14.2.1 The [Market Operator] shall report to the Regulatory Authorities at least [4
months] before the start of the Year, proposing the following parameter to be
used in the calculation of Imperfections Charges for that Year:
74
(a)
The Residual Error Volume Price (PREVy) in €/MWh for Year, y.
A.14.2.2 The [Market Operator's] report must set out any relevant research or analysis
carried out by the Market Operator and the justification for the value
proposed. The report may, and shall if so requested by the Regulatory
Authorities, include alternative values from those proposed and must set out
the arguments for and against such alternatives.
A.14.2.3 The [Market Operator] shall publish the approved value for each such
parameter within [5 Working Days] of receipt of the Regulatory Authorities'
determination or [two months] before the start of the Year to which they shall
apply whichever is the later.
A.14.3
Calculation of Residual Error Volume Charges
A.14.3.1 The Market Operator shall calculate the Residual Error Volume Charge
(CREVvγ) for each Supplier Unit, v, in each Imbalance Settlement Period, γ,
as follows:
𝐶𝑅𝐸𝑉𝑣𝛾 = 𝑀𝑖𝑛(𝑄𝑀𝐿𝐹𝑣𝛾 , 0) × 𝑃𝑅𝐸𝑉𝑦 × 𝐹𝑁𝐼𝐸𝑃𝑣𝛾
where:
(a)
PREVy is the Residual Error Volume Price for Year, y;
(b)
QMLFvγ is the Loss-Adjusted Metered Quantity for Supplier Unit, v, in
Imbalance Settlement Period, γ; and
(c)
FNIEPvγ is the Non-Interval Energy Proportion Factor for Supplier Unit
v, in Imbalance Settlement Period, γ.
A.15
CURRENCY ADJUSTMENT CHARGES
A.15.1
Purpose
A.15.1.1 The purpose of the Currency Adjustment Charge is to recover costs in
relation to the anticipated variation between the dual currencies applied in
the SEM over the Year, with adjustments for previous Years as appropriate
where costs where under or over recovered.
A.15.2
Setting Currency Adjustment Charge Parameters
A.15.2.1 The [Market Operator] shall report to the Regulatory Authorities at least [4
months] before the start of the Year, proposing the following parameters to
be used in the calculation of Currency Adjustment Charges for that Year:
(a)
The Currency Cost Price (PCCy) in €/MWh for Year, y; and
(b)
Values of the Currency Cost Charge Factor (FCCAγ) for each
Imbalance Settlement Period, γ, in Year, y.
A.15.2.2 The [Market Operator's] report must set out any relevant research or analysis
carried out by the Market Operator and the justification for the specific values
proposed. The report may, and shall if so requested by the Regulatory
Authorities, include alternative values from those proposed and must set out
the arguments for and against such alternatives.
A.15.2.3 The [Market Operator] shall publish the approved value(s) for each such
parameter within [5 Working Days] of receipt of the Regulatory Authorities'
75
determination or [two months] before the start of the Year to which they shall
apply, whichever is the later.
A.15.2.4 The [Market Operator] may, of its own accord or in response to a request
from the Regulatory Authorities, make additional interim reports to the
Regulatory Authorities during the Year, proposing revisions to the Currency
Cost Charge Factor in the event that the parameters as originally proposed
do not provide for the adequate recovery of anticipated costs and such under
recovery is such that it is not appropriate to include as an adjustment in
subsequent Years.
A.15.2.5 The Market Operator shall publish the approved revised Currency Cost
Charge Factor, and the date and time on which it comes into effect, within [5
Working Days] of receipt of the Regulatory Authorities' determination.
A.15.3
Calculation of Currency Adjustment Charges
A.15.3.1 The Market Operator shall calculate the Currency Adjustment Charge
(CCAvγ) for each Supplier Unit, v, in each Imbalance Settlement Period, γ, as
follows:
𝐶𝐶𝐴𝑣𝛾 = 𝑀𝑖𝑛(𝑄𝑀𝐿𝐹𝑣𝛾 , 0) × 𝑃𝐶𝐶𝑦 × 𝐹𝐶𝐶𝐴𝛾
where:
(a)
PCCy is the Currency Cost Price for Year, y;
(b)
QMLFvγ is the Loss-Adjusted Metered Quantity for Supplier Unit, v, in
Imbalance Settlement Period, γ; and
(c)
FCCAγ is the Currency Cost Charge Factor in Imbalance Settlement
Period, γ.
76