1. Overview of CAISO Stakeholder Process for FERC Order 764 Compliance Implementation of 15 minute scheduling and settlement
Jim Price, CAISO
Presentation to WECC Interchange Scheduling and Accounting Subcommittee
January 16, 2013

2. Proposed Implementation of Renewable Integration Market Design Changes
Fall 2013
Order 764 compliance filing
May 2013 CAISO Board decision,
Spring 2014
Dynamic Transfers: Add transmission reservation bid component & look-ahead forecast of VER availability
Implement 15-minute market
Fall 2014
Flexible ramping product in DA and RT markets
Integrated DA market & residual unit commitment

3. Executive Summary of 15-Minute Market
Adapt existing functionality to allow 15 minute schedule updates consistent with regional practices
Use three-settlement market by making Real-Time Unit Commitment (RTUC) financially binding
15-minute market replaces Hour-Ahead Scheduling Process (HASP) settlement for energy & ancillary services
Leverage Dynamic Transfers transmission reservation functionality to address hourly or sub-hourly intertie transmission for VERs?
Allow intertie Convergence Bidding if day-ahead pricing issue resolved

4. Hourly Process for Real Time Market (Straw Proposal)
T-75: Real-Time Bid Submission Deadline
T-45: Awards for Intertie Hourly Transmission Reservations
T-20: E-Tag Deadline for Hourly Intertie Transmission Profiles and
Market 1 Energy Schedules T
T = Start of the Hour
T-37.5: Start of Market 1 Optimization
Market transmission reservations in DA, HASP, & RTUC would be financially binding.
HASP energy schedules would not be financially binding.

5. 15-minute Process for Real Time Market
Financially Binding
Market 2
T-5: E-Tag deadline for Market 2 Energy Schedules
T-22.5: Self Schedule Changes for Market 2
T-7.5: Awards for Market 2 Energy Schedules T
T-22.5: Start of Market 2 Optimization
37.5 Minutes
20 Minutes
T = Start of the Hour
Second interval of RTUC optimization (currently “advisory”) becomes the binding interval in new 15-minute market, to allow e-tagging 20 minutes before start of interval

6. 5-minute Process for Real Time Market
Financially Binding
Market 1
Market 2
T+15
RTD 4
RTD 2
RTD 6
T+7.5: Start of RTD 4 Optimization
T+12.5: Awards of RTD 4 Dispatch, Start of RTD 5 Optimization
RTD 3
RTD 5
T = Start of the Hour
No changes to Real-Time Dispatch (RTD)
RTD provides operational instruction to all resources

7. All Real Time Market bids would be submitted in HASP, at T-75
Bids to economically schedule resources in 15-minute market and 5-minute economic dispatch
Energy self-schedule and/or energy bid, same as now
Ancillary services bids, same as now
No Load bids in RTUC 15-minute market or in RTD
Dynamic transfer design allows optional intertie transmission reservation bid for VERs, in excess of expected energy, to accommodate variability.
In straw proposal: Hourly transmission awards, priced at the shadow cost of intertie congestion in HASP
Use of capacity awarded in HASP is exempt from intertie congestion cost in RTUC and RTD

8. Real time self schedules may change at T-37
Real time self schedules may change at T-37.5 for every 15-minute interval
Self schedule can change in 15-minute market, e.g., due to physical or operational characteristics
VERs can update using rolling 5-minute or 15-minute granularity forecast to establish real-time schedule
Intertie changes 20 minutes before 15-minute intervals, due to physical or operational characteristics (including e-tag curtailments and reloads in other BAAs), would be limited by ISO’s transmission reservations
Changes from day-ahead to RTUC settle at RTUC price
RTUC to RTD deviations settle at the RTD price
Intertie operational adjustments to 15-minute schedule settle at RTD

9. Transmission Reservation Overview
Explicit TR bid only available to VERs with self-schedules (SS) and no ancillary services bids
Ensures ISO receives accurate expected energy so resources are not committed using inflated SS, since HASP energy not binding
Allows VERs to ensure intertie capacity is available in real-time and not allocated to hourly block schedules
For hourly block schedules,
TR bid is imbedded in energy bid
Enforce HASP constraint for same MW in each 15-min interval
For conventional 15-minute intertie or non-VER dynamics,
TR bid is embedded in energy bid
Intertie scheduling limit enforced every 15-minute interval, but advisory energy schedule can differ by 15-minute interval
TR award in HASP = avg of 15-minute advisory energy schedules

10. HASP transmission award would define priority for energy schedules and basis for congestion settlement
HASP would award financially binding hourly transmission capacity, which is then used for financially binding energy schedules and AS awards within operating hour:
Intra-hour energy schedules: 15-minute intervals
Dynamic transfer energy: dispatch by 5-minute interval
Ancillary service awards: 15-minute intervals
Unused intertie capacity would be released in each interval
Self-schedules would have higher priority within HASP transmission award
Resources using released capacity would be charged the relevant real-time intertie shadow price

11. Issue: Settlement of Transmission Reservation (TR) in multiple markets would have increased complexity
TR has separate limits for import and export directions, and considers advisory energy counterflows (e.g., 3500 MW import & 500 MW export on 3000 MW intertie)
TR would be separated into Import Right, Import Obligation, Export Right and Export Obligation
TR is unidirectional for an hour. Market participant would receive a “right” or “obligation” for each direction.
Right: For energy at or below TR, settle at original TR price. For energy exceeding TR, settle at subsequent market’s price
Obligation: Settlement principles would balance those of a “right”
Stakeholder concerns include uplift from TR settlement

12. 15-minute market may allow scheduling alternatives for reliably managing the grid
Perform market optimization based upon intertie bids
Hourly Blocks
Enforce constraint that T = T+15 = T+30 = T+45
If economic bid is not cleared, hourly block schedule is 0 MW
15-minute schedules and dynamic transfers
15 minute intervals can have different MW level
If not accepted, option to not allow economic bid in RT market
VER forecast over intertie, to allow delivery to exceed hourly avg.
How to create the VER forecast to account for variability?
Publish awarded hourly block schedules at T-45
May be able to further streamline timing
Hourly block schedules are price takers in 15-min market
Even if an economic bid submitted for hourly block schedule

13. ISO is looking for opportunities to improve timeline while remaining consistent with WECC
Accepted hourly block schedules posted by T-45
Note: binding optimization for each 15-minute interval is started afterwards
2.5 minutes is tight for updating tags for 15-minute energy schedules, after awarding intra-hour schedules
ISO investigating if solution times can be reduced
Continue to work with WECC task force and ISO stakeholders
But, tagging timeline not expected to change in near term

14. Next steps
Item
Date
Straw Proposal
October 23, 2012
Stakeholder Meeting
October 30, 2012
Technical Workshop Stakeholder Call
December 18, 2012
Revised Straw Proposal
February 5, 2013
February 12, 2013
Stakeholder Comments Due
February 26, 2012
Draft Final Proposal
March 26, 2013
April 2, 2013
Board Meeting
May 2013
Tariff Filing
September 2013
More info:
Comments on revised straw proposal may be submitted by February 26 to