Presentation on theme: "ACE Diversity Interchange (ADI)"— Presentation transcript:
1ACE Diversity Interchange (ADI) DiscussionOC MeetingMarina Del Ray, CAMark C. WillisSMUDOctober 30-31, 2008
2Current Operation Two ADI “Bubbles” within WECC NW Bubble with seven participantsSW Bubble with five participantsEach participating BA limited to 30 MW ACE deviationSuspended for concerns about system reliabilityBA operator falls back to original ACE
4Proposed Operation One ADI “Bubble” within WECC Proposal for each participating BA limited to 50 MW ACE deviation, but starting with 30 MWOne/Two Bubble operation with 14 entities will be operational by 11/1/08All entities scheduled to participate by January 2009rAgain, suspended for concerns about system reliabilityBA operator falls back to own ACE
6Reliability Concerns (1) Two “bubble” systemNo concerns for two “bubble” system currently in place
7Reliability Concerns (2) One “bubble” system concerns:Oversight responsibility of entire WECC transmission systemADI Participants unaware of all transmission impacts/conditions between NW and SW bubblesWithin California, multiple constrained 500 kV paths, many of which are dynamically rated in real-time operations, both N-S and S-NSeparation of unscheduled flow versus ADI on USF qualified WECC Paths, such as COISOL (OTC) mitigation impacted by ADI flows – scheduled and/or forced outages and resulting mitigation requirementsIncreased COI SOL (OTC) mitigation requirements
8Northern California Transmission Usage Concerns Usage of California-Oregon Transmission Project (COTP), as part of the California-Oregon Intertie (COI)Impacts multiple COI owners, including TANC, WASN, and PG&EUnscheduled transfer of energy between BAs across various TO/TOP systems
9RecommendationsOpen the ADI Operating Group to all interested WECC entitiesForm a Task Force under Operating Practices Subcommittee (OPS) as assigned by the Operating Committee to study and evaluate reliability impact to WECCTransmission Usage – Mitigation of “take of transmission”
11Talking Points (1)Parties in California, which are not participating, are not held harmless due to significant flow of ADI on the 500 kV system between the Northwest and Southwest, during “one bubble” operation, resulting in usage of other’s transmission through unscheduled transfers of energy between participating Balancing Authorities (BAs).
12Talking Points (2)Multiple WECC 500 kV paths within California are impacted both North-to-South and South-to-North during “one bubble” operation, resulting in a potential for unreliable operation and mitigation of SOL overloads, since the ADI participants are not the Transmission Operators (TOPs) of many of these paths. These WECC 500 kV paths include COI, Path 15, Path 26, West-of-River, and East-of-River, of which many of the System Operating Limits (SOLs) are dynamically determined in real-time by the respective TOP. BPA will be monitoring the COI SOL in real-time to change ADI operation from “one bubble” to “two bubble.” APS is the path operator for East-of-River.