1. 2013 Wind Conference

2. Congestion Management & Communication Processes CJ Brown

3. CONGESTION MANAGEMENT Section 1 3

4. Congestion Management Overview Transmission Loading Relief (TLR) Congestion Management Event (CME) Security Constrained Economic Dispatch (SCED) Manual Directives CLIPs 4

5. Congestion Management We manage congestion in one of two ways: –TLR (Transmission Loading Relief) event if there are curtailable (>5%) impacts other than SPP EIS Market impact –Congestion Management Events (CME) if there are no curtailable external impacts 5

6. 6 Typical Event Sequence to Mitigate Congestion The Reliability Coordinator (RC) contacts BA and or TO to confirm the SOL limit and the Real Time Loading of the flow gate The Reliability Coordinator (RC) calls a TLR event in NERC IDC. The TLR event triggers a calculation by NERC IDC to determine who needs to curtail Tags (transactions) and who needs to re-dispatch to what amount to accomplish enough relief to lower the real time loading of flow gate NERC IDC will send out curtailment instructions and relief obligations to entities that need to take action The Reliability Coordinator (RC) monitors the flow gate loading. The loading should go down because of the Tag Curtailments and re-dispatch by Markets (typically a 15-20 minute delay) The Reliability Coordinator (RC) will request more relief in NERC IDC if necessary SPP Market will accomplish its relief through Security Constraint Economic Dispatch (SCED) Communication Issue TLR in IDC Curtailments Monitor Re-issue TLR in IDC 6

7. 7 Typical Event Sequence – TLR Event 1.Flow approaches or exceeds flowgate limit 2.Reliability Coordinator calls TLR and requests relief from IDC 3.NERC IDC prescribes Tag, Network and Native Load (NNL), and/or Market Flow curtailments as appropriate 4.Constraint Manager and CAT receive Target Market Flow from IDC 5.SPP RC accepts TLR event in Constraint Manager and verifies that the effective limit is appropriate 6.SPP CAT will calculate appropriate schedule adjustments for those schedules not curtailed by IDC and send to RTOSS 7.Flowgate is activated in next Security Constrained Economic Dispatch (SCED) 8.Market System will run SCED, attempting to keep flowgate flow below effective limit 9.RC continues to monitor flowgate flow and ask for additional relief as necessary 7

8. 8 Transmission Loading Relief (TLR) Event NERC IDC RC Issues TLR SPP CAT every 15 min SPP Constraint Manager SPP MOS SCED SFT Topper / SPD Runs every 5 min RTOSS scheduling Target Market Flow to SPP CAT Adjusted Schedules Effective Limit of Constraint Sent to MOS Target Market Flow to SPP Constraint Manager Tag Curtailments 1 2 2 5 3 6 7 Dispatch Instructions and NSI values SPP RC accepts TLR 4 Market Flow Calculator Market Flow sent To NERC IDC every 15 minutes 8 2 ETAGGINGNLS 8

9. Congestion Management Event (CME) A CME is issued in the SPP EIS Market System by the SPP RC through activating a defined flowgate and setting a Target flow limit (typically SOL) for the SPP EIS Market System to maintain the flow on or below through Secure Economic Constraint 9

10. 10 Typical Event Sequence – CME 1.Flow approaches or exceeds flowgate limit 2.Reliability Coordinator verifies in NERC IDC that there are no curtailable Tags or Market relief from other Entities 3.SPP RC calls a CME event in Constraint Manager and sets effective limit 4.SPP CAT will calculate appropriate schedule adjustments for those schedules not curtailed by IDC and send to RTOSS 5.Flowgate is activated in next Security Constrained Economic Dispatch (SCED) 6.Market System will run SCED, attempting to keep flowgate flow below effective limit 7.RC continues to monitor flowgate flow and ask for additional relief as necessary (lower effective limit in Constraint Manager) Note: CME = Congestion Management Event. It only results in re-dispatch by SPP Market. It can result schedule curtailments if Market is providing counter flow to support financial schedules. CME is only allowed if there are no Tags to curtail in IDC and no Market relief from other Markets. 10

11. Congestion Management Tools used by SPP Reliability Coordinator NERC IDC OATI RC Issues CME SPP CAT OATI every 15 min Constraint Manager SPP MOS SCED SFT Topper / SPD Runs every 5 min RTOSS Scheduling OATI Adjusted Schedules Effective Limit of Constraint Sent to MOS 3 2 4 5 6 Dispatch Instructions and NSI values 1 Market Flow Calculator Alstom 15min Market Flow sent To NERC IDC every 15 minutes 7 ETAGGING NLS CME EVENT CME event Send to CAT CME = Congestion Management Event Only results in re-dispatch by SPP Market and schedule curtailments if Market is providing counter flow to support financial schedules 11

12. Security Constrained Economic Dispatch (SCED) Once a flowgate is activated in constraint manager, the SPP EIS market will redispatch all available generation to provide market flow relief EIS market runs a SCED every 5 minutes for a 10 minute out target 12

13. Manual Directives When the TLR/CME/SCED processes do not provide enough relief or if the relief cannot be provided in a timely manner, the SPP Reliability Coordinator (RC) will issue manual directives to manage congestion on the bulk electric system 13

14. CLIP Section 2 14

15. What is a CLIP? Capacity Limit Implementation process (CLIP) is a communication process in which the SPP RC will electronically communicate a deployment to a specific Non-Dispatchable Resource (NDR), which reflects a reliability output limit for that Resource. This would be comparable to a security constrained dispatch instruction provided to dispatchable Resources 15

16. Why change? Current communication of output limits for these types of Resources consists of an onerous, time- consuming process in which the deployment takes the form of a directive from the RC The purpose of CLIP is to communicate these same output limitations in the form of an electronic message that is acknowledged and monitored for implementation and efficacy 16

17. Advantages Reduce Operator/minutes consumed during the curtailment process over the current manual verbal process Greater flexibility in the issuance and release of limitations Greater focus on overall system reliability 17

18. Process Entry into the RC logging system will include a list of NDR entity names (could be common Resource names, MP names, or any common reference) that are linked to a specific email address for the real- time operational function of that resource –The required information is entity name, MW limit, and date/time 18

19. Process (cont.) When the form is completed, RC will click on a “send email” button which will send a pre-worded email message including the required information to the email link for that entity RC will initiate a pre-recorded blast call (or individual calls depending on volume to be called) to notify all impacted entities that a CLIP notification message has been sent. –Using the existing Msg911 communication tool –Text and/or computer generated voice message 19

20. Process (cont.) NDR operating entity will review and comply with the message, by first replying to the received CLIP email message and then implementing the output limitation RC shall monitor replies from recipients and ensure real-time data is consistent with the limits communicated within a timely manner (time period TBD) 20

21. Process (cont.) If RC is unable to obtain a reply, or has obtained a reply but cannot verify the resource has complied with the deployment, RC shall contact that resource and, if appropriate, issue a curtailment directive to that entity (to ensure compliance) Amendments and terminations to the output limitation will be made in the same manner as the initial limit – log, send, and verify 21

22. Development and Implementation Teams formed to address various aspects of NDR curtailment concerns CLIP project team progress: –Prototype logging pages have been developed, subject to changes based on stakeholder input –Coding is completed based on current version of logging page –Msg911 is being populated with NDR points of contact for control of their respective NDR (CLIP account) –Expected completion by end of July, depending on when final design is set (could be earlier) 22

23. Questions 23