module 5: reliability unit commitment · slide 2 day 2 reliability unit 8:30 a commitment module...
TRANSCRIPT
Module 5: Reliability Unit
Commitment
Slide 2
Day 2
Reliability Unit
8:30 A
Commitment
Module Objectives: Reliability Unit Commitment
CRR Balancing
Account
11:30
Upon completion of this module,
learners will be able to:
• Describe the overall Reliability Unit
Commitment settlement process.
• Identify Market and ERCOT actions that
impact RUC Settlements.
• Explain the RUC Make-Whole process
– Calculate Make-Whole Payment
– Calculate RUC Capacity Short Charge
• Describe and calculate the RUC Clawback
payment and charge.
Slide 3
Reliability Unit Commitment
Purpose of Reliability Unit Commitment (RUC)
It ensures:
• Enough capacity is committed to serve
the forecasted load
• Committed capacity is in the right locations
Slide 4
Reliability Unit Commitment
The Reliability Unit Commitment Process
Slide 5
Reliability Unit Commitment
Committing Enough Capacity
Slide 6
Reliability Unit Commitment
Committing Capacity in the Right Locations
Slide 7
Reliability Unit Commitment
What if ERCOT must commit additional capacity?
Slide 8
Reliability Unit Commitment
Final Results of RUC Process: Resource Commitments
Resource Decommitments
Nothing
Slide 9
Reliability Unit Commitment
Day-Ahead Reliability Unit Commitment (DRUC)
• Occurs once a day
• Ensures enough capacity committed for next Operating Day
Day 1 Day 2
1430
DRUC runs
DRUC studies all hours of Day 2
Slide 10
DRUC Study Period
Reliability Unit Commitment
Hourly Reliability Unit Commitment (HRUC)
• Occurs hourly
• Reviews all hours already studied by DRUC
Day 1 Day 2
1430
DRUC runs
HRUC runs each hour
0000 0100
0200
1600 1700
1800
Slide 11
Reliability Unit Commitment - Combined Cycle Resources
Combined Cycle Train (CCT)
• A group of Combustion Turbines (CT) and Steam Turbines (ST)
• Operate in one or more configurations
Combined Cycle Generation Resource (CCGR)
• A registered configuration of a Combined Cycle Train
• Settled at a Logical Resource Node
CCGR is offered, committed,
dispatched and settled as a
single Resource.
Slide 12
Reliability Unit Commitment - Combined Cycle Resources
CCGR 1
CCGR 2
Combined Cycle Plant
Train 1 Train 2
ST1 CT1 CT2 CT3 ST2 CT4 CT5 CT6
RUC may start an entire
CCGR or transition from one
CCGR to another
Slide 13
Reliability Unit Commitment: Settlements
• Charges and Payments for CRRs
DAM Commitment
• Make-Whole
DAM
Participation in DAM
• Energy
• AS
• PTP Obligations
Settlement of CRRs
purchased in the
Auction
RUC
Commitment
• Make-Whole
• Clawback
Decommitment
CRR Auction
• Revenue
Distribution
Slide 14
RUC Make-Whole Payment
QSE’s Representing RUC committed
resources may receive a Make-Whole
payment
Outcome
#1
What: Payment when the Real-Time revenues are less
than actual costs for a RUC-Committed Resource
Why: To ensure that a QSE recovers its costs to run a
RUC-Committed Resource
Slide 15
RUC Make-Whole Payment
Calculating RUC Make-Whole Payment
Incremental
Energy Costs
Minimum
Energy Costs
Revenues Received
$
Costs Incurred
Start-up Costs
Slide 16
RUC Make-Whole Payment
Calculating RUC Make-Whole Payment
Incremental
Energy Costs
Minimum
Energy Costs
Start-up Costs
Revenues Received
$
Costs Incurred
Real-Time
Revenues
Slide 17
RUC Make-Whole Payment
Calculating RUC Make-Whole Payment
Incremental
Energy Costs
Minimum
Energy Costs
Start-up Costs
Revenues Received
$
Costs Incurred
Real-Time
Revenues
Real-Time Revenues = RT SPP * Metered Generation
Slide 18
RUC Make-Whole Payment
What if revenues are less than cost?
Real-Time
Revenues
Revenues Received
Incremental
Energy Costs
Minimum
Energy Costs
$
Costs Incurred
Start-up Costs
Slide 19
RUC Make-Whole Payment
What if revenues are less than cost?
Real-Time
Revenues
Make-Whole Payment Incremental
Energy Costs
Minimum
Energy Costs
Revenues Received
$
Costs Incurred
Start-up Costs
Difference = Make-Whole Payment
Slide 20
RUC Make-Whole Payment
Now we re-arrange the balance sheet slightly . . .
Subtract Incremental Energy Costs from both columns
Real-Time
Revenues
Make-Whole Payment
Minimum
Energy Costs
Start-up Costs
Revenues Received
$
Costs Incurred
Incremental
Energy Costs
Incremental
Energy Costs
Slide 21
RUC Make-Whole Payment
What if revenues are less than cost?
Make-Whole Payment Minimum
Energy Costs
Start-up Costs
Revenues Received Costs Incurred
Real-Time
Revenues
Incremental
Energy Costs
Real-Time Revenues – Incremental Energy Costs
= RT SPP * Metered Generation – AIEC * Metered
Generation
Above LSL ( ) $
Slide 22
RUC Make-Whole Payment
What if revenues are less than cost?
Make-Whole Payment Minimum
Energy Costs
Start-up Costs
Revenues Received
$
Costs Incurred
Real-Time
Revenues
Incremental
Energy Costs
RUC Guaranteed Amount
Slide 23
RUC Make-Whole Payment
Trigger
#1
RUC Guaranteed
Amount ( ) ( ) < Resource
Revenues
A QSE is paid the Real-time Settlement Point Price for all
energy produced by its Resource
A QSE will also receive a Make-Whole Payment if its
Resource’s net revenues are less than its Startup and
Minimum Energy Costs
Slide 24
RUC Make-Whole Payment
Trigger
#1 ( ) ( ) < RUC Guaranteed
Amount
Resource
Revenues
Slide 25
RUC Make-Whole Payment
Calculate RUC Guaranteed Amount
RUC Guaranteed Amount = ( ) Startup costs
Minimum energy costs +
$ to Start Up
$/MWh at LSL
Startup Offer Minimum-Energy Offer
$/MWh Above LSL
Energy Offer Curve
Slide 26
Startup Price = Resource Category Generic
Startup Cost
Minimum Energy
Price =
Resource Category Generic
Minimum Energy Cost
Startup Price = Verifiable Startup Costs
Minimum Energy
Price =
Verifiable Minimum-
Energy Costs
RUC Make-Whole Payment
Calculate RUC Guaranteed Amount
Calculate Startup Costs without a Three-Part Supply Offer
Verifiable Costs Generic Costs
Slide 27
RUC Make-Whole Payment
Slide 28
RUC Make-Whole Payment
Trigger
#1 ( ) ( ) <
Startup Price (SUPR) $ 5000
RUC Startup Flag (RUCSUFLAG) 1
Minimum Energy Price (MEPR) $10/MWh
Low Sustained Limit (LSL) 20MW
Real-Time Metered Generation (RTMG) 50MWh
RUC Guaranteed
Amount
Resource
Revenues
RUCG q,r,d = (SUPR q,r,s * RUCSUFLAG q,r,s)
+ (MEPR q,r,i * Min ((LSL q,r,i * (¼)), RTMG q,r,i))
QSE4’s
Resource is
committed
for 5 hours
𝑠
𝑖
Slide 29
RUC Make-Whole Payment
Trigger
#1 ( ) ( ) < RUC Guaranteed
Amount
Resource
Revenues
RUCG = (SUPR * RUCSUFLAG) + ∑(MEPR * Min ((LSL * (¼)), RTMG ))
RUCG = ($5000 * 1) + ($10/MWh * Min(20MW * ¼h, 50MWh) * 4i/h * 5h)
= $5000 + ($10/MWh * (20MW * ¼h) * 4i/h * 5h)
= $5000 + ($10/MWh * 100MWh)
= $6000
Slide 30
RUC Make-Whole Payment
Trigger
#1 ( ) ( ) < RUC Guaranteed
Amount
Resource
Revenues
• Per QSE
• Per Resource
• Per Operating Day with RUC
Commitment
RUC Guaranteed Amount
QSE1 $4,000
QSE4 $6,000
QSE6 $8,000
Slide 31
RUC Make-Whole Payment
Slide 32
RUC Make-Whole Payment
Trigger
#1 ( ) ( ) < RUC Guaranteed
Amount
Resource
Revenues
Resource Revenues = ( ) Minimum-Energy Revenue up to LSL
Revenue Less Cost above LSL
Revenue Less Cost during QSE-
Clawback intervals
+ +
Slide 33
Calculate Resource Revenues
RUC Make-Whole Payment
Minimum-Energy revenue up to LSL
• Per QSE
• Per Resource
• Per Operating Day with RUC
Commitment $/MWh
MW
LSL
Minimum Energy Offer
SPP
Slide 34
RUC Make-Whole Payment
Calculate Resource Revenues
Minimum-Energy revenue up to LSL
Quantity = Minimum of:
Real-Time
Metered
Generation
¼ of LSL
RUC Minimum Energy Revenue
= (Price)* (Quantity)
Slide 35
Calculate Resource Revenues
RUC Make-Whole Payment
RUC Minimum-Energy Revenue
Real-Time Settlement Point
Price
Low Sustained Limit
Real-Time Metered Generation
Minimum-Energy revenue up to LSL
Determinants
RUCMEREVq,r,d = ∑ (RTSPP p,i * Min (RTMG q,r,i , (LSL q,r,i * (¼))))
Slide 36
Calculate Resource Revenues
RUC Make-Whole Payment
Minimum-Energy revenue up to LSL
RUCMEREV = ∑ (RTSPP * Min (RTMG, (LSL * (¼))))
RUCMEREV = $50/MWh * Min (50MWh, (20MW * ¼h)) * 4i/h * 5h
= $50/MWh * (20MW * ¼h) * 4i/h * 5h
= $50/MWh * 100MWh
= $5000
Slide 37
RUC Make-Whole Payment
Trigger
#1 ( ) ( ) < RUC Guaranteed
Amount
Resource
Revenues
RUC
Guaranteed
Amount
Minimum-
Energy revenue
up to LSL
Revenue Less
Cost Above LSL
During RUC-
Committed Hours
Revenue Less Cost
During QSE-
Clawback Intervals
QSE1 $4,000 $2,000
QSE4 $6,000 $5,000
QSE6 $8,000 $4,000
Slide 38
Calculate Resource Revenues
• Per QSE
• Per Resource
• Per Operating Day with
RUC Commitment
RUC Make-Whole Payment
$/MWh
MW
LSL
Costs
(AIEC)
SPP
RTMG * 4
Revenue Less Cost Above LSL During RUC-Committed Hours
Energy Offer Curves for
RUC-Committed Resources
must be priced at the
System-Wide Offer Cap
Energy Offer Curve
EOCPRCAP Revenues
SWCAP
HSL
Slide 39
Calculate Resource Revenues
RUC Make-Whole Payment
Revenue Less Cost Above LSL During RUC-Committed Hours
Revenues Costs
Energy Revenue above LSL Average Incremental Energy
Cost above LSL Voltage Support Service
Emergency Power Increase
Slide 40
Calculate Resource Revenues
RUC Make-Whole Payment
RUCEXRR q,r,d = Max {0, ∑ [RTSPPp,i * Max (0, RTMG q,r,i – (LSL q,r,i * (¼)))
+ (-1) * (VSSVARAMT q,r,i + VSSEAMT q,r,i)
+ (-1) * EMREAMT q,r,i
– RTAIEC q,r,i * Max (0, RTMG q,r,i – (LSL q,r,i * (¼)))]}
Revenue Less Cost Above LSL During RUC-Committed Hours
Additional Determinants
Revenue Less Cost Above LSL (RUCEXRR)
Voltage Support Service VAR Amount
Voltage Support Service Energy Amount
Emergency Energy Amount
Real-Time Average Incremental Energy Cost
Slide 41
Calculate Resource Revenues
RUC Make-Whole Payment
RUCEXRR q,r,d = Max {0, ∑ [RTSPPp,i * Max (0, RTMG q,r,i – (LSL q,r,i * (¼)))
+ (-1) * (VSSVARAMT q,r,i + VSSEAMT q,r,i)
+ (-1) * EMREAMT q,r,i
– RTAIEC q,r,i * Max (0, RTMG q,r,i – (LSL q,r,i * (¼)))]}
Revenue Less Cost Above LSL During RUC-Committed Hours
Real-Time Metered Generation (RTMG) 50MWh
Average Incremental Energy Cost (RTAIEC) $20/MWh
RT Settlement Point Price (RTSPP) $50/MWh
Slide 42
Calculate Resource Revenues
RUC Make-Whole Payment
RUCEXRR = Max {0, ∑ [RTSPP * Max (0, RTMG – (LSL * (¼)))
– RTAIEC * Max (0, RTMG – (LSL * (¼)))]}
RUCEXRR = Max {0, [$50/MWh * Max (0, 50MWh– (20MW* (¼)))
– $20/MWh* Max (0, 50MWh– (20MW* (¼)))] * 4i/h * 5h}
= Max {0, [$50/MWh * Max (0, 45MWh)
– $20/MWh * Max (0, 45MWh)] * 4i/h * 5h}
= Max {0, 45MWh * ($50/MWh – $20/MWh )] * 4i/h * 5h}
= $1350 * 4i/h * 5h
= $27,000
Revenue Less Cost Above LSL During RUC-Committed Hours
Slide 43
RUC Make-Whole Payment
Trigger
#1 ( ) ( ) < RUC Guaranteed
Amount
Resource
Revenues
RUC
Guaranteed
Amount
Minimum-
Energy revenue
up to LSL
Revenue Less
Cost Above LSL
During RUC-
Committed Hours
Revenue Less Cost
During QSE-
Clawback Intervals
QSE1 $4,000 $2,000 $1,000
QSE4 $6,000 $5,000 $27,000
QSE6 $8,000 $4,000 $4,000
Slide 44
Calculate Resource Revenues
• QSE-Committed Interval
• Contiguous block with one RUC-Committed hour
• QSE-Committed AFTER RUC-Commitment
Revenue Less Cost During QSE Clawback Intervals
RUC Make-Whole Payment
Hour 5 10 15 20
QSE-Committed
RUC-Committed
Slide 45
Calculate Resource Revenues
RUC Make-Whole Payment
Revenues Costs
Energy Revenue Minimum Energy Costs
Voltage Support Service Average Incremental Energy
Cost above LSL Emergency Power Increase
Revenue Less Cost During QSE Clawback Intervals
Slide 46
Calculate Resource Revenues
Revenue Less Cost During QSE Clawback Intervals
RUC Make-Whole Payment
Additional Determinants
Revenue Less Cost (RUCEXRQC)
RUCEXRQCq,r,d = Max {0, ∑ [(RTSPPp,i * RTMG q,r,i)
+ (-1) * (VSSVARAMT q,r,i + VSSEAMT q,r,i)
+ (-1) * EMREAMT q,r,i
– [MEPR q,r,i * Min (RTMG q,r,i , (LSL q,r,i * (¼)))]
– RTAIEC q,r,i * Max (0, RTMG q,r,i – (LSL q,r,i * (¼)))]}
Slide 47
Calculate Resource Revenues
Revenue Less Cost During QSE Clawback Intervals
RUC Make-Whole Payment
Real-Time Metered Generation (RTMG) 50MWh
Average Incremental Energy Cost (RTAIEC) $20/MWh
RT Settlement Point Price (RTSPP) $50/MWh
RUCEXRQCq,r,d = Max {0, ∑ [(RTSPPp,i * RTMG q,r,i)
+ (-1) * (VSSVARAMT q,r,i + VSSEAMT q,r,i)
+ (-1) * EMREAMT q,r,i
– [MEPR q,r,i * Min (RTMG q,r,i , (LSL q,r,i * (¼)))]
– RTAIEC q,r,i * Max (0, RTMG q,r,i – (LSL q,r,i * (¼)))]}
Slide 48
Calculate Resource Revenues
RUC Make-Whole Payment
RUCEXRQC = Max {0, ∑ [(RTSPP * RTMG)
– [MEPR * Min (RTMG, (LSL * (¼)))]
– RTAIEC * Max (0, RTMG – (LSL * (¼)))]}
RUCEXRQC = Max {0, [($50/MWh * 50MWh)
– [$10/MWh * Min (50MWh, (20MW * (¼)))]
– $20/MWh * Max (0, 50MWh – (20MW * (¼)))] * 4i/h * 2h}
= Max {0, [($50/MWh * 50MWh) – [$10/MWh * 5MWh]
– ($20/MWh * 45MWh)] * 4i/h * 2h}
= Max {0, [$2500 – $50 – $900] * 4i/h * 2h}
= $1550 * 4i/h * 2h = $12,400
Revenue Less Cost During QSE Clawback Intervals
Slide 49
RUC Make-Whole Payment
Trigger
#1 ( ) ( ) < RUC Guaranteed
Amount
Resource
Revenues
RUC
Guaranteed
Amount
Minimum-
Energy revenue
up to LSL
Revenue Less
Cost Above LSL
During RUC-
Committed Hours
Revenue Less Cost
During QSE-
Clawback Intervals
QSE1 $4,000 $2,000 $1,000 $0
QSE4 $6,000 $5,000 $27,000 $12,400
QSE6 $8,000 $4,000 $4,000 $8,000
Slide 50
RUC Make-Whole Payment
Trigger
#1 ( ) ( ) < RUC Guaranteed
Amount
Resource
Revenues
RUC
Guaranteed
Amount
Resource Revenues
QSE1 $4,000 $2,000 + $1,000 + $0 = $3,000
QSE4 $6,000 $5,000 + $27,000 + $12,400 = $44,400
QSE6 $8,000 $4,000 + $4,000 + $8,000 = $16,000
Slide 51
RUC Make-Whole Payment
Slide 52
RUC Make-Whole Payment
( ) ( ) < RUC Guaranteed
Amount
Resource
Revenues
RUC Guaranteed
Amount
Resource
Revenues
Eligible for Make-
Whole Payment?
QSE1 $4,000 $3,000 Yes
QSE4 $6,000 $44,400 No
QSE6 $8,000 $16,000 No
?
? ?
Outcome
#1
Trigger
#1
Slide 53
RUC Make-Whole Payment
• QSE1 Resource is RUC-
Committed
• QSE1 is eligible for a Make-
Whole Payment
RUCMWAMT = (-1) * Max (0, RUCG – RUCMEREV
– RUCEXRR – RUCEXRQC) / ∑ RUCHR
Outcome
#1
Trigger
#1
RUCHR will be set to 1 for
each RUC-Committed hour
of the day.
Slide 54
RUC Make-Whole Payment
• QSE1 is RUC-Committed
• QSE1 is eligible for a Make-
Whole Payment
Outcome
#1
Trigger
#1
RUCMWAMT = (-1) * Max (0, RUCG – RUCMEREV
– RUCEXRR – RUCEXRQC) / ∑ RUCHR
RUCMWAMT = (-1) * Max(0, $4000–$2000–$1000– 0) / 5
= - $200 per hour
Slide 55
RUC Make-Whole Payment for CCGR Transitions
DAM to RUC • RUC is contiguous to DAM commitment,
• RUC committed in different configuration,
• Train is online and generating in the RUC
committed configuration for at least 1 minute
RUC to RUC
• RUC is contiguous to previous RUC,
• RUC committed in different configuration,
• Train is online and generating in the RUC
committed configuration for at least 1 minute
SELF to RUC • RUC is contiguous to previous SELF commitment,
• RUC committed in different configuration,
• Train is online and generating in the RUC
committed configuration for at least 1 minute
1
2
3
Slide 56
CCGR 1
CCGR 2
Combined Cycle Plant
Train 1 Train 2
ST1 CT1 CT2 CT3 ST2 CT4 CT5 CT6
Transition cost is the
difference between Start-up
costs of the two CCGRs.
RUC Make-Whole Payment for CCGR Transitions
Slide 57
Trigger
#1 ( ) ( ) <
Startup Price (SUPR)
RUC Startup Flag (RUCSUFLAG)
Minimum Energy Price (MEPR)
Low Sustained Limit (LSL)
Real-Time Metered Generation (RTMG)
RUC Guaranteed
Amount
Resource
Revenues
RUCG q,r,d = ∑(SUPR q,r,s * RUCSUFLAG q,r,s)
+ ∑(Transition costs)
+ ∑(MEPR q,r,i * Min ((LSL q,r,i * (¼)), RTMG q,r,i))
Max(0, SUPR afterCCGR – SUPR beforeCCGR)
--and--
Max(0, SUPR beforeCCGR – SUPR afterCCGR) RUC-to-QSE Transition
Transition to RUC
RUC Make-Whole Payment for CCGR Transitions
Transition costs:
Slide 58
DAM Commitment
• Make-Whole
DAM
Participation in DAM
• Energy
• AS
• PTP Obligations
Settlement of CRRs
purchased in the
Auction
Reliability Unit Commitment: Settlements
RUC
RUC Commitment
• Make-Whole
• Clawback
Decommitment
• Charges and Payments for CRRs
CRR Auction
• Revenue
Distribution
Slide 59
Reliability Unit Commitment: Settlements
To remain revenue neutral, ERCOT will first try to directly
assign all costs incurred for Make-Whole Payments.
Costs are distributed based on QSE’s
shortfalls in each 15-minute interval.
RUC Commitment Period
Slide 60
RUC Capacity-Short Charge
Charge to a QSE that was capacity-
short in a RUC
Outcome
#1
What: Charge to QSEs that are capacity short
Why: Collect funds to pay the Make-Whole Payments to
eligible QSEs
Slide 61
RUC Capacity Short Charge
When a QSE does not provide enough capacity to meet its
obligations, it may be assessed a Capacity Short Charge
Capacity
Required to meet
QSE Obligations
QSE Shortfall
Capacity
arranged by
QSE
RUC Capacity-Short Charge
Slide 62
RUC Capacity Short Charge
What is included in the total QSE obligation?
• Adjusted Metered Load
• Capacity Trades where the QSE is a seller
• Energy Trades where the QSE is a seller
• Cleared DAM Energy Offers
Capacity
Required to meet
QSE Obligations
RUC Capacity-Short Charge
Slide 63
RUC Capacity Short Charge
How can a QSE arrange to meet these obligations?
• Show capacity from its Resources in its COP
• Capacity Trades where the QSE is a buyer
• Energy Trades where the QSE is a buyer
• Cleared DAM Energy bids
Capacity
arranged by
QSE
RUC Capacity-Short Charge
Slide 64
RUC Capacity Short Charge
When does ERCOT compare QSE capacity versus obligation?
• Execution of RUC
• Real-time Operations
Capacity
Required to meet
QSE Obligations
QSE Shortfall
Capacity
arranged by
QSE
RUC Capacity-Short Charge
Slide 65
RUC Capacity Short Charge
The larger QSE capacity shortfall is used for
capacity short calculations
Capacity
required to
meet QSE
Obligations
QSE Shortfall
Capacity
arranged by
QSE
QSE Shortfall
RUC (DRUC / HRUC) Real-Time
Capacity
required to
meet QSE
Obligations
Capacity
arranged by
QSE
RUC Capacity-Short Charge
Slide 66
RUC Capacity Short Charge
All QSEs who were capacity short in each RUC will pay a
portion of the RUC Make Whole Payments for that particular
RUC:
RUC Make Whole Total ( ) RUC Capacity
Shortfall
Ratio Share *
RUC Capacity
Short Charge
by 15-Minute Settlement Interval
=
RUC Capacity-Short Charge
Slide 67
Short Charge Cap
The charge to each QSE is capped at
RUC Make Whole Total
RUC Capacity Total RUC Capacity Shortfall 2 * *
Price / MW
of RUC Procurement RUC Capacity Shortfall 2 * * ( )
. . . which is the same as
RUC Capacity-Short Charge
Slide 68
RUC Capacity Short Charge
A QSE with a capacity shortfall will pay the lesser of
RUC Make Whole Total ( ) RUC Capacity
Shortfall
Ratio Share *
Price / MW
of RUC Procurement RUC Capacity Shortfall 2 * * ( )
or their cap
RUC Capacity-Short Charge
Slide 69
RUCCSAMT = (-1) * Max [(RUCSFRS * RUCMWAMTRUCTOT),
(2 * RUCSF * (RUCMWAMTRUCTOT / RUCCAPTOT))] / 4
RUCCSAMT ruc, i, q RUC Capacity Shortfall Amount
RUCSFRS ruc, i, q RUC Shortfall Ratio Share
RUCMWAMTRUCTOT ruc, h RUC Make Whole Amount Total per RUC
RUCSF ruc, i, q RUC Shortfall
RUCCAPTOT ruc, h RUC Capacity Total
RUC Capacity Short Charge
RUC Capacity-Short Charge
Slide 70
RUC Shortfall Ratio Share
• Per RUC process
• Per QSE
• Per 15-minute Interval
RUC Capacity-Short Charge
RUCSFRS ruc,i,q = RUCSF ruc,i,q / RUCSFTOT ruc,i
Determinants
RUC Shortfall Ratio Share
RUC Shortfall
RUC Shortfall Total
Slide 71
RUC Capacity-Short Charge
Determining a QSE’s RUC Shortfall
ERCOT takes Snapshots:
• QSE’s market position
each time RUC is
executed
• QSE’s market position
at end of each
Adjustment Period
DAM DRUC
Slide 72
RUC Snapshot (DRUC)
Looks at QSE’s market
position for each hour
during the RUC Study
Period
RUC Capacity-Short Charge
17 18 19 20 21 22 23 24
9 10 11 12 13 14 15 16
1 2 3 4 5 6 7 8
Slide 73
RUC Capacity-Short Charge
Adjustment Period Snapshot
Looks at QSE’s market
position at the end of
each Adjustment Period
17 18 19 20 21 22 23 24
9 10 11 12 13 14 15 16
1 2 3 4 5 6 7 8
ADJ
1
ADJ
2
ADJ
3 . . .
ADJ
6 . . .
ADJ
12
ADJ
22
. . .
. . .
Slide 74
RUC Capacity-Short Charge
Determine QSE’s RUC Shortfall
For each hour:
• ERCOT compares the
Adjustment Snapshot
with the corresponding
hour in the RUC
Snapshot
• The QSE’s RUC
shortfall is based on
the snapshot that is
the most short
17 18 19 20 21 22 23 24
9 10 11 12 13 14 15 16
1 2 3 4 5 6 7 8
ADJ
1
ADJ
2
ADJ
3
ADJ
4
ADJ
5
ADJ
6
ADJ
7
ADJ
8
ADJ
9
ADJ
10
ADJ
11
ADJ
12
ADJ
13
ADJ
14
ADJ
15
ADJ
16
ADJ
17
ADJ
18
ADJ
19
ADJ
20
ADJ
21
ADJ
22
ADJ
23
ADJ
24
Slide 75
RUC Capacity-Short Charge
RUC Shortfall
RUCSFruc,i,q = Max (0, Max (RUCSFSNAPruc,q,i, RUCSFADJruc,q,i)
– ∑ RUCCAPCREDITq,i,z)
RUC Shortfall
RUC Short Fall at Snapshot
RUC Short Fall at Adjustment
Period
RUC Capacity Credit
RUCSFSNAP
• Snapshot of the QSEs market position
each time a RUC is executed
• Different RUCSNAP for each RUC
Determinants
Prior
RUCs
Slide 76
RUC Shortfall
RUC Capacity-Short Charge
Capacity at snapshot:
High Ancillary Service Limits + DC Tie Imports
Capacity Purchase – Capacity Sales (Capacity Trades)
Day-Ahead Energy Purchases – Day-Ahead Energy Sales
QSE-to-QSE Energy Purchases – QSE-to-QSE Energy Sales
(Energy Trades)
RUCSFSNAPruc,q,i = Max (0, ((∑ RTAMLq,p,i * 4) + ∑ RTDCEXPq,p,i
– RUCCAPSNAPruc,q,i ))
Slide 77
RUC Shortfall
RUCCAPSNAPruc,q,i = ∑ HASLSNAPq,r,h
+ (RUCCPSNAPq,h – RUCCSSNAPq,h)
+ (∑ DAEPq,p,h – ∑ DAESq,p,h)
+ (∑ RTQQEPSNAPq,p,i – ∑ RTQQESSNAPq,p,i)
+ ∑ DCIMPSNAPq,p,i
RUC Capacity-Short Charge
RUC Capacity Snapshot at time
of RUC High Ancillary Service Limit at
Snapshot
RUC Capacity Purchase
Day-Ahead Energy Purchase
Day-Ahead Energy Sale
QSE-to-QSE Energy Purchase
QSE-to-QSE Energy Sale
Determinants
RUC Capacity Sale
RUCSFSNAPruc,q,i = Max (0, ((∑ RTAMLq,p,i * 4) + ∑ RTDCEXPq,p,i
– RUCCAPSNAPruc,q,i ))
DC Import at Snapshot
Real-Time DC Tie Export
(Oklaunion Exemption)
Slide 78
RUC Shortfall
RUC Capacity-Short Charge
RUCSFADJ
• Snapshot of the QSEs market position at the
end of the Adjustment period
• Built over time
• Complete at the end of the last Adjustment
period of the day
RUCSFruc,i,q = Max (0, Max (RUCSFSNAPruc,q,i, RUCSFADJruc,q,i)
– ∑ RUCCAPCREDITq,i,z) Prior
RUCs
RUC Shortfall
RUC Short Fall at Snapshot
RUC Short Fall at Adjustment
Period
RUC Capacity Credit
Determinants
Slide 79
RUC Shortfall
RUC Capacity-Short Charge
Capacity at Adjustment Period:
High Ancillary Service Limits + DC Tie Imports
Capacity Purchase – Capacity Sales (Capacity Trades)
Day-Ahead Energy Purchases – Day-Ahead Energy Sales
QSE-to-QSE Energy Purchases – QSE-to-QSE Energy Sales
(Energy Trades)
RUCSFADJruc,q,i = Max (0, ((∑ RTAMLq,p,i * 4) + ∑ RTDCEXPq,p,i
– ∑ HASLSNAPruc,q,r,h – RUCCAPADJq,i ))
WGR
Slide 80
RUC Shortfall
RUCCAPADJ q,i = ∑ HASLADJ q,r,h
+ (RUCCPADJ q,h – RUCCSADJ q,h)
+ (∑ DAEP q,p,h – ∑ DAES q,p,h)
+ (∑ RTQQEPADJ q,p,i– ∑ RTQQESADJ q,p,i)
+ ∑ DCIMPADJq,p,i
RUC Capacity-Short Charge
RUCSFADJruc,q,i = Max (0, ((∑ RTAMLq,p,i * 4) + ∑ RTDCEXPq,p,i
– ∑ HASLSNAPruc,q,r,h – RUCCAPADJq,i ))
RUC Capacity Snapshot at
Adjustment Period High Ancillary Service Limit at
Adjustment Period
RUC Capacity Purchase
Day-Ahead Energy Purchase
Day-Ahead Energy Sale
QSE-to-QSE Energy Purchase
QSE-to-QSE Energy Sale
Determinants
RUC Capacity Sale
DC Import at Adjust. Period
Real-Time DC Tie Export
(Oklaunion Exemption)
WGR
Slide 81
Activity: Now it’s your turn!
Refer to your Settlements Workbook
In a small group, respond to the questions
that relate to Scenario #RUC1
You have 10 minutes to complete your questions.
If you can not complete all questions, don’t worry
– all questions will be reviewed as a class.
Slide 82
RUC Shortfall
RUC Capacity-Short Charge
Capacity Credit
• Credit to QSEs to ensure not charged twice
for the same capacity shortage
RUCSFruc,i,q = Max (0, Max (RUCSFSNAPruc,q,i, RUCSFADJruc,q,i)
– ∑ RUCCAPCREDITq,i,z) Prior
RUCs
RUC Shortfall
RUC Short Fall at Snapshot
RUC Short Fall at Adjustment
Period
RUC Capacity Credit
Determinants
Slide 83
RUC Shortfall
RUC Capacity-Short Charge
RUC Capacity Credit
RUC Capacity Total
RUC Shortfall
RUC Shortfall Ratio Share
RUCSF
RUCCAPTOT * RUCSFRS Determinants
RUCCAPCREDIT ruc,i,q
= Min [RUCSF ruc,i,q, (RUCCAPTOT ruc,h * RUCSFRS ruc,i,q)]
Slide 84
Activity: Now it’s your turn!
Refer to your Settlements Workbook
In a small group, respond to the questions
that relate to Scenario #RUC2.
You have 5 minutes to complete your questions.
If you can not complete all questions, don’t worry
– all questions will be reviewed as a class.
Slide 85
RUC Capacity-Short Charge
• QSE3 is capacity-short for a RUC
process
• 20 MW
• Total short is
• 100 MW
RUCSFRS = RUCSF / RUCSFTOT
= 20 MW / 100 MW
= 0.20
RUC Shortfall Ratio Share
Outcome
#1
Trigger
#1
Slide 86
RUC Capacity-Short Charge
• QSE3:
– RUC Shortfall: 20 MW
– RUC Shortfall Ratio Share of: 20 %
• ERCOT-wide Values
– Total RUC Make-Whole Payments: -$800
– RUC Capacity Total: 400 MW
Trigger
#1
RUCCSAMT = (-1) * Max [(RUCSFRS * RUCMWAMTRUCTOT),
(2 * RUCSF * (RUCMWAMTRUCTOT / RUCCAPTOT))] / 4
RUCCSAMT = (-1) * Max [(.20 * $-800), (2 * 20 MW * ($-800/400 MW))] / 4
= (-1) * Max [(-$160), (-$80)] / 4
= $20
Slide 87
RUC Capacity-Short Charge
RUC Capacity Short Charge is limited to $20
by the Short Charge Cap.
Without cap, charge would have been $40.
Outcome
#1
Trigger
#1
• QSE3:
– RUC Shortfall: 20 MW
– RUC Shortfall Ratio Share of: 20 %
• ERCOT-wide Values
– Total RUC Make-Whole Payments: -$800
– RUC Capacity Total: 400 MW
Slide 88
Reliability Unit Commitment Settlements
Total RUC Make-
Whole Payments
Total Capacity-
Short Charges
... then ERCOT needs to procure additional
funds to pay the Make-Whole Payments.
If after all the Capacity-Short charges have been
collected and...
Slide 89
RUC Make-Whole Uplift Charge
Charge to all QSEs to collect enough
funds to pay the RUC Make-Whole
Payments
Outcome
#1
What:
If the revenues from the Capacity-Short Charge
don’t cover all RUC Make-Whole Payments then
additional funds will be uplifted to QSEs on a Load
Ratio Share basis
Why: Keep ERCOT revenue neutral
Slide 90
RUC Make-Whole Uplift Charge
LARUCAMTq,i = (-1) * ( RUCMWAMTTOTh / 4 + RUCCSAMTTOTi ) * LRSq,i
RUC Make-Whole Uplift Charge
RUC Make-Whole Amount Total
RUC Capacity Amount Total
Load Ratio Share
Total RUC Make-
Whole Payments / 4
Total Capacity-
Short Charges
for the interval
Uplifted at
Load Ratio Share
Determinants
Slide 91
RUC Make-Whole Uplift Charge
• QSE5 represents Load
– Load Ratio Share = .25
• ERCOT-wide Values
– Total RUC Make-Whole Payments: -$800
– RUC Capacity-Short Charge Total: $100
• ERCOT needs additional funds to pay
Make-whole Payments
Trigger
#1
LARUCAMT = (-1) * ( RUCMWAMTTOT / 4
+ RUCCSAMTTOT ) * LRS
Outcome
#1
LARUCAMT = (-1) * (- $800 / 4 + $ 100) * .25
= (-1) * ( - $100 ) * .25
= $25
Slide 92
Reliability Unit Commitment: Settlements
• Charges and Payments for CRRs
DAM Commitment
• Make-Whole
DAM
Participation in DAM
• Energy
• AS
• PTP Obligations
Settlement of CRRs
purchased in the
Auction
RUC
RUC Commitment
• Make-Whole
• Clawback
Decommitment
CRR Auction
• Revenue
Distribution
Slide 93
RUC Clawback Charge
Charge to all QSEs whose revenues
exceed the RUC Guarantee
Outcome
#1
What: Collects a portion of revenue above costs
Why: Resource was committed for reliability. Excess
revenue should be returned to Load
Slide 94
RUC Make-Whole Payment
What if revenues are greater than cost?
Minimum
Energy Costs
Start-up Costs
Revenues Received Costs Incurred
Real-Time
Revenues
Incremental
Energy Costs
$
Slide 95
RUC Make-Whole Payment
What if revenues are greater than cost?
Minimum
Energy Costs
Start-up Costs
Revenues Received
$
Costs Incurred
Clawback Charge
Real-Time
Revenues
Incremental
Energy Costs
But how does ERCOT
determine how much to
clawback?
Slide 96
RUC Clawback Charge
Clawback Factors
Three-Part Supply
Offer in DAM
No Three-Part
Supply Offer in DAM
RUC Clawback
Factor for RUC hours 50% 100%
RUC Clawback
Factor for QSE hours 0% 50%
Slide 97
RUC Clawback Charge
Trigger
#1
RUC Guaranteed
Amount
Resource
Revenues
Receive a RUC
Clawback Charge?
QSE1 $4,000 $3,000 No
QSE4 $6,000 $44,400 Yes
QSE6 $8,000 $16,000 It depends . . .
? ?
Outcome
#1
RUC Guaranteed
Amount ( ) ( ) > Resource
Revenues
?
Slide 98
RUC Clawback Charge
RUCCBAMT = [(RUCMEREV + RUCEXRR – RUCG) * RUCCBFR
+ (RUCEXRQC * RUCCBFC)] / ∑ RUCHR
RUCCBAMT q, r, h RUC Clawback Charge Amount
RUCMEREVq, r, d RUC Minimum-Energy Revenue
RUCEXRR q, r, d Revenue Less Cost Above LSL from RUC Hours
RUCG q, r, d RUC Guarantee
RUCEXRQC q, r, d Revenue Less Cost from QSE Clawback Intervals
RUCCBFR q, r, d RUC Clawback Factor for RUC-Committed Hours
RUCCBFC q, r, d RUC Clawback Factor for QSE Clawback Intervals
RUCHR RUC Hour
Calculate Clawback Amount
Slide 99
RUC Clawback Charge
RUCCBAMT = [(RUCMEREV + RUCEXRR – RUCG) * RUCCBFR
+ (RUCEXRQC * RUCCBFC)] / ∑ RUCHR
= [($5,000 + $27,000 – $6000) * 0.5
+ ($12,400 * 0)] / 5
= [$26,000 * 0.5] / 5
= $2600 per hour
Trigger
#1
• QSE4’s Resource Revenues are
greater than its RUC Guaranteed
Amount
• QSE4’s Resource was committed with
a Three-Part Supply Offer
Slide 100
RUC Clawback Payment
Payment to all QSEs that represent
Load
Outcome
#1
What: Revenue collected above costs through Clawback charge
Why: Keep ERCOT revenue neutral
Slide 101
RUC Clawback Payment
• ERCOT receives funds from
Clawback charges
• QSE5 represents Load
• Load Ratio Share (LRS) of 30%
Outcome
#1
Trigger
#1
LARUCCBAMT = (-1) * (RUCCBAMTTOT * (¼) * LRS)
= (-1) * ($2600 * (¼) * 0.30)
= (-1) * ($650 * 0.30)
= -$195
RUC Clawback Payment
= (-1) * (Hourly RUC Clawback * (¼) * QSE’s LRS)
Slide 102
DAM Commitment
• Make-Whole
DAM
Participation in DAM
• Energy
• AS
• PTP Obligations
Settlement of CRRs
purchased in the
Auction
Reliability Unit Commitment: Settlements
RUC
RUC Commitment
• Make-Whole
• Clawback
Decommitment
• Charges and Payments for CRRs
CRR Auction
• Revenue
Distribution
Slide 103
RUC Payment for Decommitment
Payment to QSE for a QSE-committed
Resource that the RUC process
decommitted
Outcome
#1
If all criteria met:
• ERCOT pays QSE for
decommittment
• Payment occurs only for
Operating Day of
decommitment
• QSE gets RUC Capacity
Credit
Slide 104
Decommitment of a QSE-Committed Resource
RUC Payment for Decommitment
Three-Part
Supply Offer Verifiable Costs Generic Costs
SUPR Startup Offer Verifiable Startup
Costs
Resource Category Generic
Startup Cost
MEPR Minimum
Energy Offer
Verifiable Minimum-
Energy Costs
Resource Category Generic
Minimum Energy Cost
RUC Decommitment Payment
• Start-up Price (SUPR)
• Less cost savings (MEPR – RTSPP), if any
• Distributed across Decommitted Hours (NCDCHR)
Slide 105
• ERCOT decommits QSE1 Unit 1
• QSE-Committed Resource
• Resource is NOT scheduled to
shutdown within the Operating
Day
RUC Payment for Decommitment
Trigger
#1
RUCDCAMT
= (-1) * Max {0, [SUPR - (Max (0, MEPR – RTSPP)
* (LSL * (¼)))]} / NCDCHR
Outcome
#1
RUCDCAMT
= (-1) * Max {0, [$1200 - (Max (0, $30 – $40)
* (10MW * (¼)))]} / 6
= (-1) * $1200 / 6 = -$200
Slide 106
• ERCOT decommits QSE1 Unit 1
• QSE-Committed Resource
• Resource is scheduled to
shutdown within the Operating
Day
RUC Payment for Decommitment
Trigger
#2
Outcome
#2
QSE will not receive
payment for decommitment
Slide 107
RUC Decommitment Charge
Charge to QSEs that represent Load Outcome
#1
What: Charge to fund Decommitment Payments
Why: Keep ERCOT revenue neutral
Slide 108
Outcome
• Resource are decommitted by the
RUC process and are eligible to
receive a decommitment payment
• QSE5 represents Load
• Load Ratio Share of 30%
RUC Decommitment Charge
Trigger
#1
RUC Decommitment Charge
= (-1) * [(RUC Decommitment Payments / 4 ) * LRS]
LARUCDCAMTq,i = (-1) * [(RUCDCAMTTOTh / 4 ) *LRS q,i ]
= (-1) * [(-$200 / 4 ) * 0.30]
= (-1) * [ -$50 * 0.30 ]
= $15
Slide 109
Module Summary
$ Describe the overall Reliability
Unit Commitment Settlement
process
$ Identify Market and ERCOT
actions that impact RUC
Settlements.
$ Calculate various charges and
payments associated with
RUC Commitments and
Decommitments
Day 2
Reliability Unit
8:30 A
Commitment
CRR Balancing
Account
11:30