1. 9/17/2012 CSWG CSWG – ERCOT Update ERCOT

2. 2 Settlements Project & Operational Updates February 27, 2012 NPRR 347: Combined Daily Invoice –Still on track for November production release –See other posted materials for additional details NPRR 322: Real-Time PTP Option Modeling –Still on track for December production release –See other posted materials for additional details NPRR 461: Energy Storage Resources –NPRR was tabled at WMS –No Updates at this time NPRR 377: Base Point Deviation Changes –Still on track for December production release –See other posted materials for additional details

3. 3 Settlements Operational Updates – Late Default Uplift Payments Overview of Issue –Payout of Default Uplift Invoices scheduled for 8/31/12 was delayed due to system issues experienced as a result of a short-payment of the Default Uplift Invoice. Root Cause –Payment Processing was delayed to give late paying entities time to make payment –When payments were received, system issues were encountered and there wasn’t time to resolve problems and still make 5pm deadline (issues have since been resolved) Resolution –All payments were made on the morning of 9-3-2012 Risk Mitigation Going Forward –We will not accept late payments after noon on the day after the due date –We plan to issue miscellaneous and default uplift invoices on Wednesdays or Tuesdays when possible to avoid processing payments on Fridays

4. 4 Zonal ADR Settlement ERCOT Recently Approved a Zonal ADR from 2007 –Needs to be invoiced by end of September Per Nodal Protocols Section 20.9(2) –If a resettlement is not practical or possible to address an adjustment required by an ADR resolution, ERCOT shall make the adjustments through a separate ADR Invoice that is produced outside of the normal Settlement system. ERCOT plans to settle this ADR using a Miscellaneous Invoice in the Nodal Systems and any remaining pending ADRs going forward whenever possible ERCOT will provide, via market, notice all ERCOT wide data needed to shadow settle: –Total ERCOT True Up Load used in LRS Uplift Calculation –Total Cost of resolved ADR February 10, 2009

5. 5 Zonal ADR Settlement Benefits of Using Nodal Systems to ERCOT –Significant reduction in staff hours and support –Less risk to time line and current nodal systems Benefits to Market Participants –QSEs don’t need to resurrect Zonal Systems to retrieve Zonal Statement, Invoice and Extract Data –Data Required to shadow should be available via QSE database (2007 True-Up Load for Operating Day) –Individual QSE True-Up load used in calculation can be requested of ERCOT Are there any concerns or questions? February 10, 2009

6. 6 Auto Pre-Pay Account Proposal Overview of Issue –Refund wires are being issued for very small amounts (less than the cost of the wire) For example: Some MPs had 6 of 7 wires for amounts under $1 on latest default uplift. In total 721 total wires were sent. 626 were under $10 –Market has raised this as a concern Proposed Solution –Prepay will be utilized going forward on small invoice amounts (less than $50) for the following invoice types: Default Uplift Invoices, Late Fee Invoices, Miscellaneous –Market Notice will be sent when refunds are automatically deposited into pre- pay account for the above invoice types –Refunds for DAM, RTM, CRR Auction and CARD invoices will never be held in pre-pay (outside of current processes) –If you would like your small invoice amounts returned via wire, please contact ERCOT Credit or your ERCOT Account Manager after the market notice is sent out

7. 7 Auto Pre-Pay Account Proposal Pre-Pay Accounts Overview –Prepay is a cash deposit account held with ERCOT by market participants –All market participants may open a prepay account –Prepay cash has no effect on cash collateral or available credit limit –No interest is earned on prepay