1. Flowgate Allocation Method
Examples of Proportional Curtailment of FIRM PTP and GTL

2. Proportional Curtailment of Firm PTP and Firm GTL – Problem Statement
Provide equal treatment of FIRM Point-to-Point (PTP) Transaction impacts and FIRM Generation-to-Load (GTL) Impacts during a TLR event
Flowgate allocation does not “downgrade” FIRM PTP and GTL transactions to NON-FIRM
TLR curtailment of FIRM contributions requires the issuance of a TLR-5 or higher
FIRM contributions are NOT curtailed in TLR-3a, TLR-3b and TLR-4
Allocations are based on forecasted/reserved (Expected) FIRM usage of flowgates up to but not exceeding the flowgate limit
Expected FIRM usage is determined in the Day-Ahead and Hour-Ahead
All Expected FIRM contributions to the flow on the flowgate are included
The total Expected FIRM contributions does not exceed the flowgate limit:
BAs and TSPs are allocated FIRM limits to their contribution on the flowgate that equals its total Expected FIRM contributions
The total Expected FIRM contributions exceeds the flowgate limit:
BAs and TSPs are allocated FIRM limits to their contribution on the flowgate proportional to their contribution
FIRM contributions are placed in two curtailment buckets – LAST TO CUT (LTC) and FIRST TO CUT (FTC)
Nomenclature:
PTP transactions: FTC = 7-F LTC = 7-FC
GTL: FTC = 7-FN LTC = 7-FCN
FIRM contributions in FTC and LTC are determined in real-time based on current system conditions
LTC: FIRM contributions in the LTC bucket are those that do NOT exceed the Expected FIRM usage of the flowgate for FIRM PTP and GTL impacts
FTC: FIRM contributions in the FTC bucket are those that exceed the Expected FIRM usage of the flowgate for FIRM PTP and GTL impacts

3. Proportional Curtailment of Firm PTP and Firm GTL - Example
Flowgate limit: 500 MW
Entity
DA/HA Firm GTL Impact
DA/HA Firm PTP Impact
GTL Firm Limit
PTP Firm Limit A
150 75 B
160
120 80 60 C D
200
100 E 40 50 20 25
Total
480
520
240
260
1,000
500

4. Proportional Curtailment of Firm PTP and Firm GTL - Example
Flowgate limit: 500 MW
Entity
GTL Firm Limit
PTP Firm Limit
RT Firm GTL Impact
RT Firm PTP Impact
Over (Under) Allocation A 75 80 5 B
120 40 60 50
(10) C D
100
(20) E 20 10 25 30
Total
240
260
310
500
550

5. FTC and LTC Calculations
TLR 5-a requires curtailment of 65 MW of FIRM transactions after exhausting all NON-FIRM curtailments
65 MW of relief will be provided pro-rata from 90 MW of FTC (7-FC and 7-FCN), using the same TLR pro-rata formulas
460 MW of LTC (7-F and 7-FN) are not curtailed
Entity
GTL Firm Limit
PTP Firm Limit
RT Firm GTL Impact
RT Firm PTP Impact
Over (Under) Allocation
FTC
LTC A 75 80 5 B
120 40 60 50
(10) C D
100
(20) E 20 10 25 30
Total
240
260
310 90
460
500
550

6. Proportional Distribution of Under-Allocated Amounts to Over-Allocated GTL/PTP – Issues To Be Resolved
Sum of all LTC (7-F and 7-FN) in Real-Time can be smaller than the flowgate limit
Only the over-allocated entities/transactions are “penalized” for over-allocating
Remaining of flowgate limit can be reassigned to over-allocated entities/transactions so that LTC equals the flowgate limit
Reduces the FTC bucket size
Distribution Proportion Options:
FIRM limits of over-allocated entities/transactions
Real-Time over-allocation impact
Real-Time impacts
Other
If TLR-5 cannot be resolved with curtailments from FTC bucket, may need to curtail pro-rata the LTC bucket
Entities/Transaction that do not over-allocate may be curtailed (see next examples)

7. Under-allocation from:
Option 2: Proportional Distribution of Under-Allocated Amounts to Over-Allocated GTL/PTP – Proportional to Firm Limit
Under-allocation from:
Entity B PTP: 10 MW
Entity D PTP: 20 MW
Entity E GTL: 10 MW
Total: 40 MW
Distribute under-allocation among over-allocating entities:
Entity A PTP: 75 MW
Entity B GTL: 80 MW
Entity D GTL: 60 MW
Entity E PTP: 25 MW
Total: 240 MW
Allocation Adjustment Ratio: (240+40)/240 = 1.17
Adjusted Firm Limit:
Entity A PTP: 75 * 1.17 = 87.8 MW
Entity B GTL: 80 * 1.17 = 93.6 MW
Entity D GTL: 60 * 1.17 = 70.2 MW
Entity E PTP: 25 * 1.17 = 29.3 MW
Total: MW

8. Over (Under) Allocation
Option 2: Proportional Distribution of Under-Allocated Amounts to Over-Allocated GTL/PTP – Proportional to Firm Limit
Adjustment factor of 1.17 applied to firm limits of over-allocated PTP/GTL (needs iterative process to use all under allocation amounts)
TLR 5-a requires curtailment of 65MW of FIRM transactions after exhausting all NON-FIRM curtailments
All 56.9 MW of FTC (7-FC and 7-FCN) will be curtailed
8.1 MW of the MW of LTC (7-F and 7-FN) will be curtailed pro-rata
Total LTC is adjusted to equal total limit of the flowgate
Entity
GTL Firm Limit
PTP Firm Limit
RT Firm GTL Impact
RT Firm PTP Impact
Over (Under) Allocation
Adj. GTL F-Limit
Adj. PTP F-Limit
FTC
LTC A 75 80 5
87.8 B
120 40
93.6
26.4 60 50
(10) C D
100
70.2
29.8
(20) E 20 10 25 30
29.3
0.7
Total
240
260
310
253.8
247.1
56.9
493.1
500
550
500.9

9. Under-allocation from:
Option 3: Proportional Distribution of Under-Allocated Amounts to Over-Allocated GTL/PTP – Proportional to Real-Time Over-Allocation
Under-allocation from:
Entity B PTP: 10 MW
Entity D PTP: 20 MW
Entity E GTL: 10 MW
Total: 40 MW
Distribute under-allocation among over-allocating entities:
Entity A PTP: 5 MW
Entity B GTL: 40 MW
Entity D GTL: 40 MW
Entity E PTP: 5 MW
Total: 90 MW
Allocation Adjustment Ratio: 40/90 = 0.44
Adjusted Firm Limit:
Entity A PTP: *0.44 = 77.2 MW
Entity B GTL: *0.44 = 97.6 MW
Entity D GTL: *0.44 = 77.6 MW
Entity E PTP: *0.44 = 27.2 MW
Total: MW

10. Over (Under) Allocation
Option 3: Proportional Distribution of Under-Allocated Amounts to Over-Allocated GTL/PTP – Proportional to Real-Time Over Allocation
Adjustment factor of 0.44 applied to over-allocated firm limits (no iterative process needed)
TLR 5-a requires curtailment of 65MW of FIRM transactions after exhausting all NON-FIRM curtailments
All 50.4 MW of FTC (7-FC and 7-FCN) will be curtailed
14.6 MW of the MW of LTC (7-F and 7-FN) will be curtailed pro-rata
Total LTC is adjusted to equal total limit of the flowgate
Entity
GTL Firm Limit
PTP Firm Limit
RT Firm GTL Impact
RT Firm PTP Impact
Over (Under) Allocation
Adj. GTL F-Limit
Adj. PTP F-Limit
FTC
LTC A 75 80 5
77.2
2.8 B
120 40
97.6
22.4 60 50
(10) C D
100
77.6
(20) E 20 10 25 30
27.2
Total
240
260
310
265.2
234.4
50.4
499.6
500
550