1. May 11, 2012 RPG meeting 2012 5YTP Scope and Process – RPG Comments

2. 2 RPG meetingMay 11, 2012 2012 5YTP Scope – RPG comments  Section 1 Five-Year Transmission Plan Goals  1.1 Identify projects to meet needs for ERCOT Operating Guide Section 5 and NERC TPL- 001, TPL-002, TPL-003 and TPL-004 Reliability Standards in the years 2013, 2014, 2015 and 2017  Section 2 Assumptions 2.1 Transmission Topology  2.1.3 Dynamic ratings will be used for the economic portion of the analysis, but will not be used for the reliability portion Suggested change  Static ratings will be used for the economic portion of the analysis as a proxy to offset the impact of historically typical transmission unavailability associated with construction and maintenance clearances. New  Transmission Interfaces will be modeled with historically typical limits (i.e. Valley Import Limit is historically typical 1,100 MVA, West – North historical typical 2,000 MVA)

3. 3 RPG meetingMay 11, 2012 2012 5YTP Scope – RPG comments  Section 2.2 Generation  Wind plants will be dispatched at the SSWG base case levels for the reliability analysis except as noted below  Wind plants will be dispatched according to AWS Truepower profiles selected for each plant for the economic analysis Suggested change  Wind Generation Resources will be dispatched as follows: Reliability Analysis: At zero MW in the Super Zone (described in 2.3 below) being studied, and dispatched in the remaining Super Zone at the SSWG base case levels  Economic Analysis: Wind plants will be dispatched according to AWS Truepower profiles selected for each plant for the economic analysis

4. 4 RPG meetingMay 11, 2012 2012 5YTP Scope – RPG comments  Section 2.2 Generation New  Run a sensitivity study removing units which have a signed generation interconnection agreement but have not provided required security and a notice to proceed.  All existing generation plants and units with a signed generation interconnection agreement by the start of the analysis will be used in the study with the below exceptions Suggested change  All future generation plants and units will be modeled in the study, if they meet the following conditions: 1) Interconnecting Entity (IE) has notified ERCOT that it has given the Transmission Service Provider (TSP) a financial commitment sufficient to fund the interconnection facilities and Notice to proceed with the construction of the interconnection, 2) notified ERCOT that it has obtained all required air permits from the Texas Commission on Environmental Quality (TCEQ), and 3) demonstrated that it has obtained the rights to sufficient water to operate the facility (if needed).

5. 5 RPG meetingMay 11, 2012 2012 5YTP Scope – RPG comments  Section 2.3 Load  The load will be evaluated by weather zone. The higher of 1. the aggregated weather zone load in the SSWG base cases or 2. the ERCOT weather zone load forecast will be used for the reliability portion of the analysis. In addition, if there is not sufficient generation to meet the load and reserve requirements, the base cases may be the split into multiple study regions, defined by combinations of weather zones. For each region studied, the corresponding weather zone demand will be set to the higher of the either the SSWG or ERCOT econometric demand forecast. For the weather zone outside the study area the demand will be set to the ERCOT econometric forecast. Suggested change  The load will be evaluated by weather zone. The studies will be performed using ERCOT’s published 90 th percentile high-temperature driven load forecasts within the group of weather zones being studies (Super Zone), with the remaining weather zones set to ERCOT’s econometric expected coincident peak load level. The following weather zone groupings define each Super Zone which will be studied: Super Zone North: Comprised of Weather Zones NorthCentral, North, West, and FarWest Super Zone South: Comprised of Weather Zones SouthCentral, South, East and C  If there is not sufficient generation to meet the load and reserve requirements, mothballed units will be placed in-service in the reliability analysis per the SSWG Procedure Manual Section 4.3.3. If necessary, loads outside of the study area may be reduced until the load and reserve requirements are met.

6. 6 RPG meetingMay 11, 2012 2012 5YTP Scope – RPG comments  Section 3.2 Reliability Analysis New  As a case validation method, compare preliminary and final study findings of reliability violations to actual facilities that experienced an insecure state lasting at least 30 minutes during previous peak load conditions.

7. 7 RPG meetingMay 11, 2012 2012 5YTP Scope – RPG comments Other General:  Section 2.2 Generation  General - Will the generation dispatch include the new responsive reserve and regulation requirements and the non-spinning reserve requirement?  ERCOT should consider using the average SPP of the load zone for the Wind Production Cost instead of 0$/MWh? Wind generators on the coast would use the south load zone $, wind generators in the west would use the west load zone $, etc… If not, ERCOT should consider doing a sensitivity study using the average SPP of the load zone for the Wind Production Cost?  Section 2.2 Load  Reasonable variations in load specifically recent events in West Texas or other areas where the future load is growing faster than the current processes can see or plan for; this could be a check that TP for the area have an opportunity to adjust the load

8. 8 RPG meetingMay 11, 2012 2012 5YTP Scope – RPG comments Other General:  Section 2.4 Contingency  Single generation unit - Will a combined cycle unit be considered a single unit?  Section 3.1 Condition the SSWG base case topology  General - The TSPs tune the voltages in the cases created by SSWG. Who will tune the voltages in the cases created by MOD?  Section 3.4 Economic Analysis  General - Will ERCOT use chronic congestion experienced in 2011 as an input into the economic analysis?

9. 9 RPG meetingMay 11, 2012 2012 5YTP Scope Implication of DC tie Modeling (NPRR 405) Paragraphs 9 and 10 of Nodal Protocol Section 4.4.4  (9) DC Tie Load is considered as Load for daily and hourly reliability studies, and settled as Adjusted Metered Load (AML). DC Tie Load is curtailed prior to other Load on the ERCOT System due to transmission constraints as set forth in Section 6.5.9.3.4, Emergency Notice, and during Energy Emergency Alert (EEA) events as set forth in 6.5.9.4.2, EEA Levels.  (10) DC Tie Load shall neither be curtailed during the Adjustment Period, nor for more than one hour at a time, except for the purpose of maintaining reliability.  Should the DC ties be modeled as loads (full export) in our planning reliability studies (5YTP) ?

10. 10 Regional Planning GroupNovember 14, 2008 Questions?