Congestion Management Working Group WMS update 11/7/2012

CRR Annual Auction The CRR transaction limit of 2,500 for year 1 of CRR Annual Auction avoided the bid rationing process. Matt Mereness reported 133,540 transactions were submitted (168,552 were available). Active CRR Account Holders has risen to 145 from 97 as in the 2011 annual auction Year-one of the CRR Annual Auction is finished running Peak Week Day took 210 hours to solve.

Over-mitigation Mitigation is being applied to broadly – Mitigating resources in step 2 that are meeting load balance, however have no impact on non competitive constraint – “Tie breaking” logic QGSRs tied with the marginal Step 1 resources receive small base point requiring them to come online at LSL when they are not really needed by system, which in turn causes price depression. ERCOT will draft their proposed solution in the form of a Nodal Protocol Revision Request to be reviewed at the December 14 th CMWG meeting. – Includes running the CCT every 5-minutes in real-time to determine which resources impact a constraint – Add a feature in the Energy Offer Curve cap logic that would differentiate QGSRs offers – Key items for the Constraint Competitiveness Test being discussed: Eliminate ECI on export side and price floors; 3-player test (Shams); consider concentration of the MWs needed (Clayton)