1 April 2010 TX SET Timeline Project Conceptualization 11 weeks Market Requirements 12 weeks ERCOT Requirements 12 weeks Conceptual Design 6 weeks Detail Design 10 weeks Build & Unit Test 16 weeks Market Flight Test 7 weeks ERCOT UAT 16 weeks Go Live TX SET Release Timeline spans 75 weeks (18 months) on average Project Planning 28 weeks Project Execution 28 weeks June 2010 – Aug 2010 Feb 2011 – Mar 2011 Mar 2011 – June 2011 Nov 2010 – Jan 2011 Oct 2011 – Jan 2012 Feb 2012 – April 2012 June 2011 – Sept 2011 Aug 2010 – Oct 2010

2 TX SET Project Delivery Project Conceptualization (11 weeks) –ERCOT Governance Process - Develop PRR and NPRR and route through the appropriate approvals (requires Market Participation and agreement) –Project Charter – Details the business objectives and high-level in-scope and out-of-scope items (requires Market Participation) –Time Cost Estimation – High-level estimates of ERCOT costs –Cost Benefit Analysis – High-level estimates combined with ERCOT and Market benefits (requires Market Participation) –Project Plan – Resource commitments from ERCOT, scope definition April 2010

3 TX SET Project Delivery Project Planning –Market Requirements (6 weeks) – require multiple brainstorming sessions followed by time for review and sessions for refinement by all Market Participants (requires Market Participation) –ERCOT Requirements (8 weeks) - ERCOT business analyst meets with multiple business teams to capture requirements, review and refine –Conceptual Design (6 weeks) - Development team produces high-level design documents serving to validate and clarify any ambiguity in requirements. Multiple business teams review, refine and confirm. April 2010

4 TX SET Project Delivery Project Planning cont … –Detail Design (10 weeks) - Documents the specific details of system changes required to support the requirements defined by the Market and ERCOT as well as interdependencies of ERCOT systems and the necessary deployment architecture Technical Architecture – Documents the architecture additions and/or changes required to support the detailed system design and project requirements – requires review and approval from ERCOT Enterprise Architecture System Security Requirements and Risk Assessment – Documents the applicable security controls and any associated system security risks resulting from approved system design and architecture Schedule Development for Execution Phase and Resource Planning - collects resource estimates, drafts and reviews schedule and commits resources for execution phase April 2010

5 TX SET Project Delivery Project Execution –Build & Unit Test (16 weeks) - Development efforts and testing of individual components in independent environments for ERCOT and Market Participants –Test Scripts – Requires multiple review sessions with Market and ERCOT staff to ensure adequate test scenarios are defined (requires Market Participation) –Integration Testing – ERCOT and Market Participants functional testing of components integrated in the same environment –UAT (16 weeks) –Testing of the solution by both ERCOT and the Market Regression Testing – ERCOT and Market Participants testing to ensure no impacts to previously existing functionality –Market Flight Test (7 weeks) – Market testing of the solution involves both ERCOT and Market Participants April 2010

6 TX SET Project Delivery Go Live –Go Live - ERCOT and Market Participants release of project into production environment Requires ERCOT and Market coordination to create production implementation schedule Requires ERCOT and Market coordination for production conversion April 2010