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SeTrans Grid Company Market Structure and Operations. Proposed Market Structure. Assumptions. Market Features. Control Area Concept. Ancillary Services Markets. Firm Transmission Rights. Congestion Management. Assumptions.
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Proposed Market Structure • Assumptions. • Market Features. • Control Area Concept. • Ancillary Services Markets. • Firm Transmission Rights. • Congestion Management. 2001 SERC Conference
Assumptions • RTO will be the control area operator. • RTO will not operate a Power Exchange. • All generators under RTO authority will be subject to redispatch under emergency conditions. • RTO will be the Security Coordinator. 2001 SERC Conference
Assumptions • RTO will have authority and responsibility to maintain system reliability: • Normal Conditions. • Emergency Conditions. • Sufficient resources will be under RTO control to respond to all credible system contingencies. 2001 SERC Conference
RTO Market Features • Three Time Periods: - Day Ahead -Hour Ahead -Real Time • Day Ahead submission of hourly balanced schedules with optional hourly adjustments. • Mandatory settlement for all real time deviations from schedule. • Real Time settlements based on Locational Marginal Price (LMP) at generator or load bus. 2001 SERC Conference
RTO Market Features • Ancillary Services acquired through bid based markets. • Transmission service reserved on Contract Path basis. • Firm transmission rights awarded on flowgate basis, not contract path. 2001 SERC Conference
Balancing Entity A Balancing Entity Southern Company Balancing Entity B Balancing Entity C Control Area Concept TVA VACAR Southern Subregion RTO IPP Entergy IPP IPP FRCC
Control Area Concept • Normal operations supported by Ancillary Services purchased from bid based market. • Emergency operations: • Reliability situations which can not be resolved using market mechanisms, i.e. insufficient ancillary services bid. • Mandatory redispatch of all generators. • Mandatory curtailment. 2001 SERC Conference
Ancillary Services • Bid-Based Ancillary Services Market. • FERC Ancillary Services: • Scheduling and Dispatch Services. • Reactive and Voltage Control. • Spinning Reserves. • Supplemental Reserves. • Regulation. • Energy Imbalance. • Congestion Management. • Black Start/System Restoration. 2001 SERC Conference
Ancillary Markets Operated • Capacity and Energy Markets. • Reactive and Voltage Control. • Interconnection agreements and contracts. • Spinning Reserve. • Supplemental Reserve. • Regulation. • Energy Imbalance. 2001 SERC Conference
Day Ahead Process Timeline • Initial Submittal of Balanced Schedules 11:00 AM • - Initial RTO Analysis • Initial Posting of Day Ahead Projections 12:00 PM - Transmission Customer Analysis • Adjustment Submittal 1:00 PM - Final RTO Analysis • Final Posting of Day Ahead Projections 2:00 PM - Day Ahead Settlement Process Closed Initial Submittal Initial Posting Adjustment Submittal Final Posting TC Analysis RTO Analysis RTO Analysis 11:00 AM 12:00 PM 1:00 PM 2:00 PM Iteration 1 Iteration 2
Hour Ahead Process Timeline • Submittal of Balanced Schedules 2 Hours Prior to Real Time • Initial RTO Analysis • Final Posting of Hour Ahead Data 1 Hour Prior to Real Time • Hour Ahead Settlement Process Closed • Final Transmission Customer Adjustments • Scheduling Window Closes Twenty Minutes Prior to Real Time • Transaction Scheduling • Real Time Operations Scheduling Window Closes Initial Submittal Final Posting Real Time Operations RTO Analysis TC Adjustments 2 Hours Prior to Real Time Twenty Minutes Prior to Real Time 1 Hour Prior to Real Time Real Time
Firm Transmission Rights • All firm transmission service customers will receive Firm Transmission Rights (FTRs). • FTRs represent rights to specific flowgate capacity along the contract path specified. • Flowgates are transmission facilities or interfaces that may reasonably be expected to experience congestion during certain time periods. 2001 SERC Conference
Firm Transmission Rights POR TVA Duke FG 1 FG 3 FG 2 FG 4 FG 5 FG 6 Entergy FG 7 FRCC POD
Firm Transmission Rights • Possession of an FTR confers specific rights if the flowgatebecomes congested: • Priority for avoiding redispatch cost. • Priority for avoiding physical curtailment. • FTRs may be freely traded subject to registration with the RTO. The RTO will operate a secondary market. • FTRs may be used for any transaction, not just the one they were awarded for. 2001 SERC Conference
Congestion Management • Required when system parameters exceed security limits. • May apply to day ahead, real time operations or contingency conditions. • System parameters can include: • Current Flows. • Voltages. • Dynamic Stability Limits. 2001 SERC Conference
Congestion Management • When congestion occurs, non-firm service customers may: • Pay voluntary redispatch costs (if a redispatch solution is available). • Purchase Firm Transmission Rights (and thus become firm transmission customers). • Physically curtail transaction. 2001 SERC Conference
Congestion Management • When congestion occurs, firm service customers: • Pay mandatory redispatch costs or reduce schedule(s). • If no redispatch solution exists, all customers may have to physically curtail (based on priority). 2001 SERC Conference
Congestion Management • Congestion may be caused by external loop or parallel flows. • To the extent that these can be identified, efforts will be made to curtail these flows prior to calling for internal redispatch. • External parties may be given the option of voluntary redispatch. • External parties that hold Firm Transmission Rights will be treated as any other firm service customers. 2001 SERC Conference
Locational Marginal Pricing • LMPs will be calculated on the following schedule: • Following initial submission of day ahead schedules. • Following submission of hour ahead schedules. • Hourly for real time settlement process. • Projected LMP prices for the next 24 hours will be published each hour. 2001 SERC Conference
Locational Marginal Pricing • Locational Marginal Price: The marginal cost of supplying the next increment of electric demand at a specific location on the electric power network, taking into account both generation marginal cost and the physical aspects of the transmission system. 2001 SERC Conference
Locational Marginal Pricing • LMP will be used to price all energy deviations from schedule regardless of cause, including: • Energy Imbalance. • Redispatch. • Ancillary Services. 2001 SERC Conference
LMP Example $25 $20 $10 $40 $15 SAMPLE SYSTEM (lossless system assumed) Load = 50 MW each 70 MW each
Uncongested System Total Load = 250 MW Marginal unit 70MW 40 MW 70 MW $25 $20 $10 100 MW Limit 60 MW Flow $40 70 MW LMP= $25 $15 • Settlement • All Loads and Generators are Bilateral • LMP of $25 Charged to Deviations From Scheduled Amount Load = 50 MW each Generator = 70 MW each Marginal Generator
Congested System Left Load = 150 MW Right Load = 100 MW Partial Congestion Marginal unit Marginal unit 50 MW 60 MW $25 70 MW $20 $10 50 MW Limit 50 MW Flow 0 MW LMP= $20 LMP= $25 $40 70 MW $15 • Settlement • LMP of $20 Charged to Deviations From Scheduled Amount on Left • LMP of $25 Charged to Deviations From Scheduled Amount on Right Marginal Generator Load = 50 MW each Generator = 70 MW each
Fully Congested System Complete Congestion Left Load = 150 MW Right Load = 100 MW Marginal unit 70 MW 10 MW $25 70 MW $20 Marginal unit $10 0 MW Limit 0 MW Flow 30 MW LMP= $40 LMP= $20 $40 70 MW $15 • Settlement • LMP of $20 Charged to Deviations From Scheduled Amount on Left • LMP of $40 Charged to Deviations From Scheduled Amount on Right Load = 50 MW each Generator = 70 MW each Marginal Generator
FTR Congestion Hedging TTCA-B = 1000 MW B A Firm FTRs = 1000 MW Total Scheduled Flow = 1100 MW Firm Scheduled = 800 MW Non Firm Scheduled = 300 MW Redispatch Required = 100 MW 2001 SERC Conference
FTR Congestion Hedging $20/MW $40/MW A B 100 MW 100MW RTO Pays Generator B $40/MW*100 MW = $4000 RTO Receives From Generator A $20/MW*100 MW = $2000 RTO Cash Flow = $2000-$4000 = -$2000 RTO is Revenue Short Congestion Costs of $2000 must be recovered from transactions 2001 SERC Conference
FTR Congestion Hedging IDRA = $20/MW IDRB = $40/MW B A TTC Allocated to FTR Owners Scheduled FTR = 800 MW < 1000 MW Firm Customers allocated NO congestion Cost All Congestion Costs Directly Assigned to Non-Firm 2001 SERC Conference
FTR Congestion Hedging IDRA = $20/MW IDRB = $40/MW A B Non-Firm Charged Congestion Allowable Non-firm Flow = 1000 - 800 = 200 Scheduled Non-firm = 300 MW Non-firm Congestion Cost = (Scheduled - Allowed)*(IDRB-IDRA) Non-firm CC = (300-200)*(40-20) = $2000 RTO Congestion Costs = $2000 RTO is Revenue Neutral 2001 SERC Conference
FTR Congestion Hedging IDRA = $20/MW IDRB = $40/MW A B Congestion Costs Paid by FTR Customers = $0 Congestion Costs Paid by Non FTR Customers = $2000 RTO Congestion Costs = $2000 The Model Directly Assigns Congestion Costs to Those Creating the Congestion 2001 SERC Conference
FTR Congestion Hedging TTCA-B = 600 MW A B Firm FTRs = 1000 MW Total Scheduled Flow = 1100MW Firm Scheduled = 800 MW Non Firm Scheduled = 300 MW Additional redispatch required = 500 MW. Additional redispatch available = 200 MW. 1. Curtail 300 MW nonfirm. 2. Use 200 MW of redispatch for firm. 3. If TTC drops below 600 MW, curtail firm on a priority basis.
Model Summary • LMPs are charged/paid based on deviations from schedule. • Neither a Pool nor a PX are required. • Bilateral contracts are the primary power market. • Congestion costs are paid only by those creating the congestion. 2001 SERC Conference
Model Summary • Firm customers make no congestion cost payments unless they cause the congestion. • FTRs allocated based on flowgate impact. • FTRs can be used for alternate paths that impact the same flowgate. • FTRs provide incentive to sell unused rights into market. 2001 SERC Conference