Transcript 03. Overview RT Co-Opt and Multi-Interval

Overview of ERCOT Concept Paper on
Real-Time Co-optimization of Energy & Ancillary
Services
&
Multi-Interval Real-Time Market
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Multi-Interval Real-Time Market
A. Enable the active participation of additional Resources in
Real-Time price formation rather than passively
responding
•
Load Resources with “blocky” deployable MWs and temporal
constraints are candidates
B. The Multi-Interval RT Market is cleared (normally) every
5-minutes, in which, the market clearing process
considers a set of consecutive 5-minute intervals, of up
to a maximum of 30 minutes, starting with the current 5minute interval.
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Multi-Interval Real-Time Market
RT Market Execution: Depicts the start and end times of the clearing process and the length of symbol is indicative of maximum time
allowed to clear market
Interval where the LMPs, MW awards (energy, AS) and Commitment Instructions are ALL binding commitment
instructions
Intervals where ONLY Commitment Instructions are binding and the LMPs and MW awards (energy, AS) are indicative
8:40 8:45 8:50 8:55 9:00 9:05 9:10 9:15 9:20 9:25 9:30 9:35
Sequence of Multi-Interval RT
Markets
Analysis window of rolling 30 minutes
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Multi-Interval Real-Time Market
C. Pricing run required to
•
•
Treat “blocky” MW deployment as dispatchable and hence
participate in price formation
Pricing run also required to allow ramp constrained Resources to
participate in price formation
D. Settlements
•
Make whole payments from:
1.
2.
•
Resources that are ramp-constrained and are awarded a binding
Base Point that is uneconomical for them
Resources that are committed for a future interval and, after
following the commitment instruction, the binding RT LMPs (and
MCPCs) for that interval are uneconomical for them
Uplift arises from the two above forms of make whole payment
1.
Instead of directly going to the uplift mechanism, should the “shorts”
be charged first?
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Multi-Interval Real-Time Market
E. Issues:
•
Load Forecast is critical input. Improvements required
•
Clearing Engine run time to solve within acceptable
timeframe is a challenge
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Real-Time energy and Ancillary Service Co-Optimization
A. Full fledged Real-Time (RT) energy and Ancillary Service
(AS) co-optimization utilizing Operating Reserve Demand
Curve (ORDC)
1. Replaces the current approximation to RT energy and AS cooptimization using ORDC
B. Enables appropriate scarcity pricing through the
valuation of operating reserves
1. Current approximation to RT energy and AS co-optimization also
enables scarcity pricing
C. Allows Market participants to adjust their energy and AS
portfolios in Real-Time
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Real-Time energy and Ancillary Service Co-Optimization
D. Real-Time Market nominally cleared every 5 minutes
(same as current)
1. Energy Awards (Base Points) to meet ERCOT system wide
demand – same as current
2. Energy Imbalance settlements unchanged – same as current
3. LMPs at every electrical bus and Settlement point – same as
current
NEW
4. AS (Reg-Up, Reg-Down, RRS, Non-Spin) awards to meet full AS
requirements
5. AS Imbalance settlements – similar to current AS Imbalance
settlements for ORDC, but each type of AS (Reg-Up, Reg-Down,
RRS, Non-Spin) will have its own AS imbalance settlements
6. AS MCPCs for each AS type
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Real-Time energy and Ancillary Service Co-Optimization
E. “HASL – free” operation
1. Concept of HASL does not exist, i.e. no instruction from ERCOT
to release HASL. This eliminates the current hand shaking
procedure involved with the ERCOT instructed release of HASL
2. Resource Specific Offers for AS ($/MW price and MW quantity)
can be updated at any time (or until very close to Real-Time)
3. Existence of Resource Specific AS Offers at time of market
clearing is considered intenty to provide AS if awarded and
be deployed potentially at the same time
1.
Communication delays, or different pathways for information may lead to
situations where QSE representing Resource is instructed to deploy AS
before the QSE gets notification of AS award
4. Key performance metric is the ability to follow Base Point
Instructions
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Real-Time energy and Ancillary Service Co-Optimization
E. “HASL – free” operation - continued
5. Different treatment for RRS from Load Resources with High Set
Under Frequency Relay
•
•
Treated as price takers in each 5 minutes clearing (cannot potentially
arm/disarm relay if RRS awarded/not awarded?)
Deployment of RRS from Load Resources will remain the same (local
frequency relay operation, ERCOT instructed deployment of RRS)
6. Telemetry/XML submissions requirements from Resources will
change
•
•
Telemetered AS responsibility from QSE not required
May require changes to AS Offer submission rules (deadline, etc.)
7. Pricing run will still be required to price out deployment of RRS
from Load Resources, ERS deployment, LSL from RUC/RMR
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Real-Time energy and Ancillary Service Co-Optimization
F. Settlements
– Does not introduce any NEW make whole or uplift
– For Real-Time, AS Imbalance settlement concept (similar concept
to Real-Time Energy Imbalance settlement) to settle the RealTime AS awards
G. Some Issues for further discussion
F. Use of ORDC
G. Coordination of values ($/MWh or $/MW/h) of VOLL, Power
Balance Penalty, and AS demand curves
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