ERCOT Transmission Planning Overview Cathey Carter, Tim McGinnis, Ping Yan, Phung Nguyen ERCOT Transmission Planning

Objectives Identify the new generation coming into ERCOT grid in the next 18 months Identify newly implemented Generic Transmission Constraints (GTC) in ERCOT system Identify remaining reliability issues that potentially require Constraint Management Plans (CMP) for 2016 Identify major 345-kV projects expected to be in-service from April 2016 to September 2017 Recognize future system issues identified and studies being done for the Valley and Houston areas

Transmission Planning Responsibilities Generation Interconnection or Change Request (GINR) Regional Transmission Plan (RTP) Regional Planning Group (RPG) Reviews Other Studies such as Long-Term System Assessment (LTSA), Reliability Must Run (RMR) Studies, Dynamic Studies, NERC Compliance Studies, etc

Generation Interconnection Requests As of November 12, 2015, the total capacity under study in ERCOT with the Commercial Operation Date (COD) by the end of June 2017 is 34281 MW The break down of the capacity by generator types: Gas: 9691 MW Solar: 6411 MW Wind: 18159 MW Storage: 20 MW

Planning Guide Section 6.9 Executed Standard Generation Interconnection Agreement (SGIA) with Transmission Service Provider (TSP) Provided sufficient financial commitment and notice to proceed Air permit / water rights (conventional units only)

Project Status * Based on GINR information as of November 12, 2015

Future Generators (MW) with SGIA * Based on GINR information as of November 12, 2015

Generators Completed Planning Requirements 1 Briscoe Wind (150 MW) 2 Green Pastures W (300 MW) 3 Shannon Wind (200 MW) 4 Barilla Solar 1B (7MW) 5 Downie Ranch Solar (95 MW) 6 Javelina Wind (250 MW) 7 Sendero Wind (78 MW) 8 Cameron County Wind (165 MW) 9 PHR Peakers (390 MW) 10 Baytown Chiller (270 MW) * Based on GINR information as of November 12, 2015

ERCOT Solar Penetration Study Since the majority of the solar projects undergoing interconnection studies are located in the West/Far West weather zones where the transmission system is relatively weak, ERCOT is in the process of performing a solar penetration study The objective of the study is to assess impacts of the solar projects on ERCOT’s current transmission system and get a high level understanding of the needed transmission upgrades to accommodate the solar projects should they come online as planned

ERCOT Solar Penetration Study The solar penetration study will study the solar projects in three stages: Stage 1: 1352 MW of Solar Projects will be studied Stage 2: 5166 MW of Solar Projects will be studied Stage 3: 8979 MW of Solar Projects will be studied The deliverable of the study is the identification of transmission projects to address issues found for each stage of solar projects At this time ERCOT does not plan to recommend any specific projects from the study findings. Rather, the study will be used to inform future planning studies

Generic Transmission Constraints Generic Transmission Constraints (GTCs) are used in reliability and market analyses pursuant to Section 3.10.7.6 Use of Generic Transmission Constraints and Generic Transmission Limits of the ERCOT Nodal Protocols Generic Transmission Limits (GTLs) associated with GTCs are posted on the MIS Secure Area The need for GTC is typically identified to manage stability, voltage, and other constraints that cannot otherwise be modeled directly in ERCOT’s powerflow and contingency analysis applications.

GTCs Implemented in ERCOT in 2015 The Zorillo to Ajo GTC has been effective since February 27, 2015 The Panhandle GTC has been effective since July 31, 2015 The Laredo GTC has been effective since September 9, 2015 The Liston GTC is effective starting November 12, 2015 The Molina GTC is effective as of December 01, 2015

Location of the GTCs

Future Generators (MW) with SGIA * Based on GINR information as of November 12, 2015

From Station (Acronym) Zorillo to Ajo GTC The Zorillo to Ajo GTC constraint limits the flow on the Zorillo – Ajo 345 kV line: The constraint represents a stability limit associated with coastal wind farms connecting to the Ajo substation The instability includes undamped and high magnitude oscillations during high generation output following a three phase to ground fault event The interface name associated with this GTC in the Network Operations Model is “ZO_AJO” Line Acronym From Station (Acronym) To Station (Acronym) Voltage Rating (kV) Line Rating (MVA) AJO_ZORILL1 Ajo (AJO) Zorillo (ZORILLO) 345 1852* * Line is dynamically rated. Listed rating is static nominal rating.

From Station (Acronym) Panhandle GTC The Panhandle GTC is an interface constraint consisting of the following transmission lines: The constraint represents a voltage stability limit associated with flows out of the Panhandle area The interface name associated with this GTC in the Network Operations Model is “PNHNDL” Line Acronym From Station (Acronym) To Station (Acronym) Voltage Rating (kV) Line Rating (MVA) RILEY_TESLA1 Tesla (TESLA) Riley (RILEY) 345 2988* JIMTRE_TESLA2 Jim Treece (JIMTREEC) EDITHC_TESLA1 Edith Clarke (EDITHCLA) EDITHC_TESLA2 COTTON_EDITHC3 Cottonwood (W_CW_345) COTTON_EDITHC4 T-301 Dermott Switch (DMTSW) 1792** T-302 * Line is dynamically rated. Listed rating is static nominal rating. ** Line is dynamically rated and jointly owned; most limiting static nominal rating is provided

From Station (Acronym) Laredo GTC The Laredo GTC is an interface constraint consisting of the following transmission lines: The constraint represents a voltage stability limit associated with flows into the Laredo area The interface name associated with this GTC in the Network Operations Model is “LAREDO” Line Acronym From Station (Acronym) To Station (Acronym) Voltage Rating (kV) Line Rating (MVA) LOBO_SANMGS1 San Miguel (SANMIGL) Lobo (LOBO) 345 1793 HOLCOM_NLARSW1 Holcomb (HOLCOMB) North Laredo Switch (NLARSW) 138 177* NLARSW_PILONC1 Piloncillo (PILONCIL) 122 LAQUIN_LOBO1 La Quinta (LAQUINTA) 347* JAVALT_MOLINA1 Javalina Tap (JAVALTAP) Molina (MOLINA) 257* FREER_LOBO1 Freer (FREER) 69 38 * Line is dynamically rated. Listed rating is static nominal rating.

From Station (Acronym) Liston GTC The Liston GTC is an interface constraint consisting of the following transmission lines : The constraint represents a control instability limit associated with generators in the Liston area The interface name associated with this GTC in the Network Operations Model is “LISTON” Line Acronym From Station (Acronym) To Station (Acronym) Voltage Rating (kV) Line Rating (MVA) BATES_LISTON1 Liston (LISTON) Bates (BATES) 138 257* GARZA_MIGHOW1 Mighoward Tap (MIGHOWTP) Garza (GARZA) * Line is dynamically rated. Listed rating is static nominal rating.

From Station (Acronym) Molina GTC The Molina GTC constraint limits the flow on the Aguilare – Javalina 138 kV line: The constraint represents a control instability limit associated with generators in the Molina area The interface name associated with this GTC in the Network Operations Model is “MOLINA” Line Acronym From Station (Acronym) To Station (Acronym) Voltage Rating (kV) Line Rating (MVA) AGUILAR_JAVLTP Aguilare (AGUILAR) Javalina Tap (JAVALTAP) 138 251* * Line is dynamically rated and jointly owned; most limiting static nominal rating is provided

Objectives Identify the new generation coming into ERCOT grid in the next 18 months Identify newly implemented Generic Transmission Constraints (GTC) in ERCOT system Identify remaining reliability issues that potentially require Constraint Management Plans (CMP) for 2016 Identify major 345-kV projects expected to be in-service from April 2016 to September 2017 Recognize future system issues identified and studies being done for the Valley and Houston areas

How Power Outages Might Occur Snakes, birds, trees, equipment failure, storms, people... It is necessary to plan ahead to make the grid as strong as possible well before a series of events occur that could trigger an emergency. For example, this event occurred in July, 2014 in Massachusetts: http://www.youtube.com/watch?v=bePE8aSMa1A

Hot Air Balloon Hits Power Line

2015 Regional Transmission Plan (RTP) The RTP is ERCOT’s annual transmission assessment to identify transmission needs over the next six years ERCOT staff coordinates the planning activities with ERCOT’s Regional Planning Group (RPG) and the Transmission Planners (TPs) Identify Corrective Action Plans such as Reliability projects and Constraint Management Plans (CMPs) in accordance with NERC Reliability Standards and ERCOT reliability criteria Identify Economic projects per the ERCOT Economic Planning Criteria

2015 RTP – Potential CMPs Some reliability issues were not mitigated with projects Project may have had construction delays Recent system changes such as new loads Mostly 69kV constraints Mostly 2016 Summer Constraint Management Plan Operational actions to resolve transmission security violations Includes Mitigation Plans, Pre-Contingency Action Plans, Remedial Action Plans, and Temporary Outage Action Plans RTP identifies potential CMPs with input from TPs Operations Planning will consider the potential CMPs when finalizing the list of CMPs for 2016

2015 RTP – Potential CMPs This list contains only those CMPs involving single circuit or common structure contingencies

2015 RTP – Potential CMPs

Objectives Identify the new generation coming into ERCOT grid in the next 18 months Identify newly implemented Generic Transmission Constraints (GTC) in ERCOT system Identify remaining reliability issues that potentially require Constraint Management Plans (CMP) for 2016 Identify major 345-kV projects expected to be in-service from April 2016 to September 2017 Recognize future system issues identified and studies being done for the Valley and Houston areas

345-kV Projects Under Construction As projects are planned and constructed, Transmission Service Providers (TSPs) provide transmission data to ERCOT via a web-based modeling application (Model on Demand) Projected In-Service Dates are included in the data This data can be used to update models and also to develop a list of projects that are expected to be In-Service for a given timeframe (in this case, the next 18 months) Major 345-kV projects such as new lines and transformers were included in the compiled list, while other projects such as transformer replacements, terminal upgrades, or reactors are not

345-kV Projects Under Construction * Based on project tracking information as of October 1, 2015

345-kV Projects Under Construction

Objectives Identify the new generation coming into ERCOT grid in the next 18 months Identify newly implemented Generic Transmission Constraints (GTC) in ERCOT system Identify remaining reliability issues that potentially require Constraint Management Plans (CMP) for 2016 Identify major 345-kV projects expected to be in-service from April 2016 to September 2017 Recognize future system issues identified and studies being done for the Valley and Houston areas

Lower Rio Grande Valley (LRGV) Study Add Lobo - North Edinburg - Loma Alta 345-kV lines (June 2016) The entire Frontera Facility will not be available to ERCOT after the Lobo - North Edinburg - Loma Alta lines are energized (2016) Legend Existing 345kV line Existing substation In progress 345kV line Proposed 345kV line Proposed 345kV sub Proposed 345kV xfr Proposed SVC

Lower Rio Grande Valley (LRGV) Study 2021 Summer Peak Load: 2,752 MW Nat gas gen: 1,470 MW Reliability Violations included a voltage stability limitation during contingencies involving generation near the North Edinburg sub Transmission projects submitted to ERCOT’s RPG April 16, 2015: American Electric Power Service Corporation (AEPSC) September 15, 2015: CPS Energy and Sharyland ERCOT is expecting to complete studies by March 25, 2016

Lower Rio Grande Valley (LRGV) Study AEPSC Recommendation: North Hill – Ajo – Zia 345-kV Lines (≈125 miles) & 3 Static VAR Compensators (SVCs). $621.5 Million North Hill Zia Legend Existing 345kV line Existing substation In progress 345kV line Proposed 345kV line Proposed 345kV sub Proposed 345kV xfr Proposed SVC

Lower Rio Grande Valley (LRGV) Study CPS Energy/Sharyland Recommended Solution: Elm Creek - Palmito dbl ckt 345kV lines (≈280 miles), La Palma - Palmito 345kV line (≈30 miles), multiple 345-kV transformers, SVCs, etc. $643.68 Million Legend Existing 345kV line Existing substation In progress 345kV line Proposed 345kV line Proposed 345kV sub Proposed 345kV xfr Proposed SVC

AEPSC Hidalgo-Starr Study Significant load growth in Hidalgo County which is served through various 138-kV circuits Thermal violations observed on the 138-kV system for various contingencies in the 2017 and 2020 Summer Peak study years Transmission expansion project submitted to ERCOT’s RPG July 13, 2015: AEPSC Hidalgo-Starr Transmission Project AEPSC Recommended Solution Cut Stewart Road substation into N.Edinburg – Loma Alta 345-kV line (≈10 miles) Add two 345/138-kV transformers at Stewart Road Add Pomelo – Frontera 345-kV line (≈23 miles) Add 345/138-kV transformer at Frontera Split and reconfigure 138-kV lines at locations including West Edinburg and Pharr Perform related substation construction $151 Million In Service Date: TBD

AEPSC Hidalgo-Starr Study The 345-kV system may be extended into the Frontera and Stewart Rd substations. Legend Existing 345kV line Existing substation In progress 345kV line Proposed 345kV line Proposed 345kV sub Proposed 345kV xfr Proposed SVC Pomelo Stewart Rd

Houston Import Project ERCOT has determined that there will be a need for additional import capacity into the Houston region by 2018 Population in the Houston region is expected to grow at a rate of over 100,000 new residents per year The Houston metro area has almost 40% of the nation’s petrochemical manufacturing capacity The Port of Houston has ranked first among U.S. seaports in terms of import tonnage for 22 consecutive years The Houston region represents approximately ¼ of the total ERCOT peak system load

Houston Import Project Transmission Projects were submitted to the RPG in 2013 ERCOT planning criteria violations occurred in the 2018 peak load case The Singleton-Zenith 345-kV lines were overloaded under N-1 Multiple 345-kV lines were overloaded and there were low voltage conditions under G-1 and N-1

Houston Import Project ERCOT evaluated 21 project alternatives The study included: Power Transfer Analysis Production Cost Savings analysis In 2014, the ERCOT Board of Directors (BOD) endorsed the recommended solution: Limestone – Gibbons Creek – Zenith double circuit 345-kV lines (≈130 miles)

Jones Creek Project Freeport LNG Development, Limited Partnership announced a natural gas liquefaction and export project on Quintana Island 690 MW total load (no self-serve generation) Additional 146 MW load with 82 MW self-serve generation at pretreatment plant (not on Quintana Island) Load will come on between Q3 2017 and Q3 2018 Transmission expansion project submitted to ERCOT’s Regional Planning Group July 2014: CenterPoint Energy submitted a project proposal to the RPG that includes new Jones Creek 345/138-kV station and multiple 138-kV system upgrades in the Freeport area

Jones Creek Project Planning criteria violations occurred at 2019 peak load levels The Freeport – Quintana - Surfside 138-kV lines were overloaded under N-1 There was voltage collapse during under X-1 and N-1 (Both Dow 345/138-kV transformers outaged)

Jones Creek Project In February 2015, the ERCOT BOD endorsed this solution: Construct a new 345/138-kV Jones Creek Substation Install two new 345/138-kV transformers at Jones Creek Split/reconfigure/upgrade multiple 138-kV facilities $77.8 Million. In-service May 2017 Jones Creek

Questions ?

Objectives Identify the new generation coming into ERCOT grid in the next 18 months Identify newly implemented Generic Transmission Constraints (GTC) in ERCOT system Identify remaining reliability issues that potentially require Constraint Management Plans (CMP) for 2016 Identify major 345-kV projects expected to be in-service from April 2016 to September 2017 Recognize future system issues identified and studies being done for the Valley and Houston areas