ERCOT Nodal Market Flowchart

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ERCOT Nodal Market Flowchart
Day-Ahead Scheduling Period
Adjustment Period
Timeline
Operating Period
Real-Time Operations
Settlement
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ERCOT Market Flowchart
ERCOT Load Forecast Preliminary Forecast of
Available Generation Determination of Ancillary
Service Requirements Transmission Outages and
Units Forecast
ERCOT 8 Day Look-Ahead Model
Day-Ahead Market Phase I (Implementation of
Auction DAM)
Clearing Agent clears Bids and offers
using Simultaneous Feasibility Test based on
security constrained network model
Clearing Agent sends contract prices,
contract volumes and schedule Information to
Market participants.
Market Participants Submit bids to purchase and
offers to sell CRRs, energy and
bilaterals w/congestion charge limits
Day-Ahead Scheduling Period
Available CRRs
Self-Arrangement Bids A/S Bids
Other Bilateral Schedules and Resource Bids
Submitted To ERCOT (3-Part Bids if uncommitted
energy bid Curves for all others)
Clearing Agent submits Schedules to ERCOT
Day-Ahead Ancillary Service Procurement
ERCOT Day-Ahead Reliability Unit
Commitment Resources Instructions (e.g., hours
run time, minimum load)
Units Running From Previous Days
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ERCOT Market Flowchart
ERCOT Load Forecast Preliminary Forecast of
Available Generation Determination of Ancillary
Service Requirements Transmission Outages and
Units Forecast
ERCOT 7 Day Look-Ahead Model
Day-Ahead Market Phase II (Implementation of
EH-DAM)
CRRs
No
Market Participants Submit bids to purchase and
offers to sell CRRs, energy and
bilaterals w/congestion charge limits
Hold to RT?
Offer to Sell?
Yes
Sold
Offer No Sale
Day-Ahead Scheduling Period
Reduce XMSN Limits by CRRs in RT
No Offer
Available CRRs
Calc LMPs Settle EH-DAM
Self-Arrangement Bids A/S Bids
Other Bilateral Schedules and Resource Bids
Submitted To ERCOT (3-Part Bids if uncommitted
energy bid Curves for all others)
EH-DAM Schedules Actual Committed Units, Unit
Capacity Credits Obligations
Day-Ahead Ancillary Service Procurement
ERCOT Day-Ahead Reliability Unit
Commitment Resources Instructions (e.g., hours
run time, minimum load)
Units Running From Previous Days
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ERCOT Market Flowchart
Day-Ahead Scheduling Period
Adjust Energy Resource Bids For Uncommitted
Resources
Adjustment Period
Bilateral Schedules for Transfer of Obligations
Commit/Decommit Units with ERCOT approval
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ERCOT Market Flowchart
Adjustment Period
Revised 24 Hour Load Forecast
Hourly Security Analysis (Perform Six Hours
Forward Look 1 Hrs. Ahead of Real-Time)
Forced Outages Transmission Generation
Actual Generation Loading
New A/S Schedules
Unit Commitment Decision Commit/Decommit Quick
Start and Other Available Units
Award Additional Necessary A/S
Operating Period
Re-Opened A/S Market With Procurement
Self-Arrangement of Incremental A/S Need
Real-Time Process (See Next Page)
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ERCOT Market Flowchart
Real-Time Telemetry
Operating Period
Real-time Security Analysis (See Next Slide)
Load/Frequency Control
Operator Remedial Actions
System AS Capacity Monitor
Real-Time LMP Unit Base Point Calculator
Operating PeriodReal-Time Operations
A/S Provider Capacity Monitor
Reserve Deployment Instructions
Unit MW Base Points And /mwh Lambdas 4 Second
Signal
Regulation Instructions (Portfolio Signal) 4
Second Signal
QSE
Automatic Dispatch Of Regulation Imbalance
Energy
Manual Dispatches
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ERCOT Market Flowchart
Operating Period
Load/Frequency Control
Real-Time Security Analysis
Dynamic Transmission Limit Calculations
Real Time Weather
Network Topology
SCADA Telemetry
Real-Time Lambdas Unit BasePoint Calculator
Real-Time Operations
State Estimator
SCADA Alarm Processor
SCED
Operator Contingency Selection
Security Analysis
Post 5 Minute LMPs To Market
Remedial Action
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ERCOT Market Flowchart
Operating Period/ Real-Time Operations
Evaluate QSE and Resource Performance
Evaluate ERCOT Performance (Includes NERC
Compliance, meeting Protocol requirements such as
regulation Crossing zero every 10 minutes, timely
Awarding of Balancing Bids, appropriate Deploymen
t of generation resources)
Settle Imbalance Energy From Day-Ahead Financial
Schedules Settle Congestion Costs for All
Other Nodal Injections Sinks Pay CRR Holders
Settlement
Determine if Resource Deployments meet criteria
to set LMP