2015 TEPPC Study Program1

2015 TEPPC Study Program

DRAFT for TAS Review

Studies Work Group

April 3, 2015

155 North 400 West, Suite 200

Salt Lake City, Utah 84103-1114

Western Electricity Coordinating Council

2015 TEPPC Study Program1

Table of Contents

Appendix A – 2015 TEPPC Study Program

Base Cases

High Priority Studies

Medium or Low Priority Studies

“Conditional” Studies

Studies with yet to be Determined Priority

Introduction

This document presents and discusses details of the 2015 Transmission Expansion Planning Policy Committee (TEPPC) Study Program. TEPPC is tasked with conducting a biennial transmission system study program (Study Program) as a component of WECC’s regional transmission assessment planning process (RTEP). The goals, processes and procedures of the Study Program were crafted, in part, as a response to FERC Order No. 890 “Preventing Undue Discrimination and Preference in Transmission Service” (Order 890). One of the provisions of Order 890 is to give transmission system stakeholders the right to request a defined number of high priority economic studies annually.Recognizing that enforcement of this provision on a provider-by-provider basis would be costly, and could result in duplicative studiesand could hinder sub-regional and regional coordination, FERC also allows transmission providers and stakeholders to cluster or batch requests for economic planning studies to enable efficient performance of such studies. The TEPPC Study Program, along with studies done by Transmission Providers and Sub-regional Planning Groups take together satisfy the requirements of Order 890’s economic planning studies requirement, as appropriate to best meet the needs of stakeholder economic study requests. The Study Program is based on inputs from multiple sources, including economic study requests from stakeholders that arise out of the provisions of Order 890.

The 2015 Study Program has been prepared under the provisions of the TEPPC Regional Transmission Expansion Planning (RTEP) Protocol (TEPPC Transmission Planning Protocol). The Study Program for this yearis the first year of a new biennial transmission study program. The goal of the biennial study program is to produce sets of congestion study results that are analyzed and used in the preparation of a WECC Interconnection-wide Transmission Plan (WECC Plan). The Study Program for this year details the analytical activities that TEPPC will perform to evaluate theneeds and weaknesses of transmission system of the Western Interconnection under various conditions for future 10-year and 20-year time horizons. Two time horizons will be studied as part of the 2014 Study Program.

  • Ten-year Horizon (2024) – The 10-year time horizon will be used to evaluate the impact of options to meet existing and potential future energy policies, and the impact technology changes and external drivers may have on transmission needs and costs in the Western Interconnection. All 10-year studies start with the 10-yearCommon Case, ensuring a common point of reference exists for all 10-year studies performed and analyzedin the process of creatinga WECC Plan. The Common Case is based on stakeholder-provided assumptions regarding loads, generation and transmission. The 10-year studies are conducted with a production cost model.
  • 20-year Horizon (2034) – A set of studies representing potential energy futures for a 20-year study horizon will be evaluated using the WECC Long-Term Planning Tool (LTPT), a capital expansion model (CXM). A desired outcome, in part, of the long-term studies is to identify those decisions that need to be made now in order to realize the potential energy futures being evaluated.

The Study Program is developed to:

1)Respond to requests received under the provisions of the TEPPC Transmission Planning Protocol.

2)Incorporate relevant study needs of regional planning groups, state authorities, transmission providers and generators.

3)Develop needed models for production cost and transmission utilization studies.

4)Support the objectives of the WECC Strategic Plan by providing useful transmission insights into the implications of major policy and technology changes for the future of the western power system.

The list of proposed studies outlined in this document was prepared by the Technical Advisory Subcommittee (TAS) from an initial clustering and consolidation of study requests prepared by the Studies Work Group (SWG) for this planning year. The list includes study requests submitted under the provisions of the TEPPC Transmission Planning Protocol during the request window period that ended January 31 of this planning year (Study Request Open Season). The result of this process is the proposed Study Program described herein. Prior to finalizing the Study Program, TEPPC will review stakeholder feedback and requests for reconsideration.

Transmission Planning and the Study Program

The objective of TEPPC’s Study Program transmission expansion studies is to provide an Interconnection-wide perspective on future transmission needs of the Western Interconnection. This information is useful to transmission project developers, energy service providers, regulators, policymakers, and other parties involved in making public policy and investment decisions that impact the Western Interconnection.[Transmission Provider??] Since TEPPC’s work is one component of the many activities involved in the planning, building, and operating of the transmission system, this section first covers WECC’s planning activities. Following this, there is a brief description of the adaptive planning cycle of the TEPPC Transmission Planning Protocol. Finally, the specific study methodology that will be used for this year’s TEPPC Study Program is described.

TEPPC’s work complements and coordinates with other WECC transmission planning related activities. These include state and provincial integrated resource planning (IRP), regional planning group plans, state and provincial renewable portfolio standards (RPS), analyses of renewables integration by the National Renewable Energy Laboratory (NREL), the Western Electricity Industry Leaders (WEIL) studies, and the numerous initiatives by the Western Governors’ Association (WGA).[Transmission Providers; Western Planning Regions??]

Purpose of Transmission Planning

Electric power networks are a unique part of our national infrastructure. With current technology, long-distance high-voltage lines are not buried, so they become a visible part of the landscape through which they pass. Transmission facilities also have very long lives, so decisions made today have long-lasting effects. Therefore, the objective of long-term transmission planning is to make the best network design decisions today after considering possible future needs and expansion options. Few, if any, 10-year or 20-year transmission plans will come to fruition as originally conceived. However, by planning for possible future needs, flexibility is built into the network’s design that allows options to be exercised and adaptation to occur as future conditions are revealed.

TEPPC’s activities are an integral part of the Western Interconnection’s overall approach to Interconnection-wide planning of the transmission system, which has two major aspects for consideration:

1)System reliability—characterized as “keeping the lights on” while responding in a predictable fashion to both planned and unplanned outages to generation and transmission system elements.

2)System utilization,—a measure of the economic performance of the transmission system. System production cost studies and associated capital cost estimates for those studies provide answers to the question, “While operating within the bounds of reliable operation, how well does the transmission system perform to deliver electricity services to consumers at a reasonable cost?”

Regional Transmission Expansion Planning

WECC’s RTEP project is described in the TEPPC Transmission Planning Protocol. The TEPPC Transmission Planning Protocol governs the transmission planning process used by TEPPC to support transmission providers in meeting the transmission planning obligations of Attachment K to the transmission providers’ Open Access Transmission Tariffs (OATT).

TEPPC Study Program Development

The Study Program for this year represents the first year of a new biennial RTEP study cycle. The development of the annual Study Program is an adaptive process that uses results from previous study programs to not only improve the quality of the cases, but to add new models or modify study methodology to continually improve the results produced by each successive study program. This expansion of planning activity is made possible, in part, by lessons learned in previous study programs.

Figure 1 is taken from the TEPPC Transmission Planning Protocol and presents the process for developing a Study Program. The inputs presented in Figure 1 are used by the SWG to develop a consolidated list of studies. In preparing the consolidated list, the SWG looks for opportunities to combine requests to meet multiple needs with a reduced number of studies. The consolidated list is reviewed by TAS and forwarded to TEPPC for consideration. All stakeholders, including the parties who submitted study requests, are invited to attend TEPPC meetings and participate in the prioritization discussion. The consolidated list of studies is then adjusted based on the TEPPC discussion and posted for review. Stakeholders are given an opportunity to request reconsideration of TEPPC’s proposed Study Program before it is finalized.

Figure 1. Study Program Development Process

Lessons Learned from Previous Study Cycles

Results from previous Study Programs will be used to create the current Study Program which will inform the WECC Plan. As such, results produced from previousstudy programs will provide an analytical foundation from which new studies can be performed and analyzed for use in the creation of a new WECC Plan. The list of proposed studies outlined in this document has been developed and prioritized to reflect this goal.

In addition, the goal of each study program is to improve on previous study programs. As such, the studies outlined in this document consider new issues/topics of Interconnection-wide significance, and address gaps left by past study programs and plans.

Other Study Activities

In addition to the studies described in this report, TEPPC has ongoing activities that support its Study Program effort.

•WECC staff led effort to conduct historical analysis of system utilization.[1]

•The SWG and Data Work Group (DWG) build the study databases needed for simulation studies.

•The Modeling Work Group (MWG) develops improved simulation models based on needs identified in past studies.

Each of these activities is an important element of TEPPC’s adaptive approach to developing transmission planning studies.

Types of Study Cases

Prior to the formation of TEPPC, a number of Western Interconnection transmission studies were completed using production cost simulations. These studies stimulated an interest in economic evaluation of transmission expansion and led to the formation of TEPPC. These studies were also influential in triggering an interest in a number of major transmission projects now being developed across the Western Interconnection. However, one of the concerns expressed regarding the early studies was the inclusion of potentially redundant generation and transmission expansion proposals. The presence of surplus generation and transmission tended to mask possible congestion – eliminating it before it could be identified. To avoid this problem, the SWG uses a study methodology consisting of two types of study cases: portfolio cases and expansion cases. The relationship between the two types of study cases is shown in Figure 2 for a set of illustrative, hypothetical cases.

Figure 2. Simulation Study Case Relationships

Common Case and Reference Case

The Common Case and Reference Case are the Study Cases from which all other Study Cases are built. The Common Case is the 10-year “expected future” based on a compilation of all the existing and 10-year projected load, resources, and transmission. The Reference Case is the 20-year “possible energy future”extending the trajectory of the 10-year Common Case assumptions another ten years into the future.

Portfolio Cases

Portfolio Cases (PC) are developed to represent a possible pattern of future load and resource development. The type and location of incremental resources will be different among portfolio cases, based on the analysis of the WECC Loads & Resources information. Load and general policy changes can also be included to reflect varying futures. For the network topology, portfolio cases use a representation of the existing transmission plus new transmission for which construction is sufficiently certain in the given horizon year. From the Common Case, additional Portfolio Cases are developed that represent other possible patterns of load and resource developments.

The portfolio cases provide a hypothetical portfolio of resources that balance load and generation. In past TEPPC studies, the incremental resources were added in three groups: 1) renewable resources needed to meet the renewable portfolio standard (RPS) of a given state in the study year, 2) more likely planned resources listed in LRS reports, and 3) enough conventional generation to achieve load-resource balance. Evaluation of a portfolio case is used to identify binding constraints that may suggest what additional transmission is needed to alleviate congestion. In other words, these are used to evaluate the impact of different future market, regulatory, and policy conditions on the need for transmission network expansion.

Sensitivity Cases

Sensitivity Cases are typically a set of studies consists of “single-parameter” changes within the load, resource, and transmission assumptions of a Study Case. By changing a single variable or specific set of variables such as hydro conditions or load, this set of studies informs stakeholders about how deviations in the study case assumptions can impact on the initial study case’s results.

Expansion Cases [ISO Comments: should this be more appropriate for inter-regional planning considerations?]

Expansion Cases (EC) are developed from portfolio cases by adding incremental transmission and/or storage projects, or any other incremental piece of infrastructure that may provide operational or economic benefit. This is the second step in the transmission study analysis to investigate the effect that various transmission expansion options may have on system utilization. By reporting the impact on system utilization and a capital cost estimate of different alternatives, stakeholders will be more able to judge their interest in various projects and provide a basis for further project studies.

Power Flow Export Cases

Power Flow (PF)Export Cases are power flow models (PFM) that representthesystem condition of a specific hour within a production cost study case’s simulation.

Study Cases

“Study Case” generically describes other Study Cases that don’t fall into the above mentioned types of study cases. Varies numerous inputs and/or assumptions of a specific study case to evaluate the aggregate impacts (typically built from the Common Case)

Elements and Themes of the this Study Program

The consolidated list of proposed study cases prepared by the SWG and TAS is provided in Appendix A. Because of the large number of study requests, only a limited number of study cases were given a high priority, indicating the intent to complete them within the current study year. The remaining studies were ranked as medium priority and will be completed as time permits.

An explanation of each proposed study cluster and general study approach is located at the beginning of Appendix A. Once the Study Program is approved by TEPPC, the study formulation effort is kicked off in a “scoping call” where the exact study specifications, timeline, and central study questions are developed by SWG leadership, WECC staff, and the study requestor(s). TEPPC will rely on a number of study requestors to provide data needed for its study cases. Requests for this data will be communicated clearly and in a timely fashion via the Study Scoping Form (Appendix D) that is filled out in the scoping calls.

General Study Themes

This section describes the general study themes of the study programs (Appendices A and B). The study themes represent the areas of interest where TEPPC would like to focus its attention while leveraging both WECC analysis and studies being conducted by others.

Studying the Important Challenges to the Grid

Stakeholder requests influenced the Study Program to examine some important trends that pose major challenges to the grid over the 10-year and 20-year study horizons. In particular, key topics to be addressed are increasing levels of distributed generation, increasing levels of renewable generation to meet evolving policy objectives, and the potential increase in coal plant retirements or displacements (e.g., not explicitly retired as part of a study assumption, but rather displaced due to an indirect study assumption such as high carbon costs) in the Western Interconnection. These scenarios strive to raise and explore important questions about the reliability[How is this to be done through economic studies?] of the grid and whether the future system has sufficient flexibility to meet increased levels of variable generation.[Again, how is this to be done through economic studies] The use of transmission expansions to mitigate future congestionstresses introduced by load growth and resource build-outs has and should continue to be the focus of interconnection-wide planning efforts. In addition, it is important to explore and study how new resource and transmission technologies (e.g., storage facilities, enhancements to thermal ramping capabilities, synchrophasors, advantages of DC transmission lines) can be used to mitigate future issues.

Unifying Planning Efforts and Tools

The desire to analyze the reliability and flexibility of the future grid requires adding new innovative tools of analysis to transmission expansion planning. TEPPC has augmented its traditional use of the production cost model (PCM) with a capital expansion model (CXM) by integrating a Long Term Planning Tool (LTPT) developed by WECC to study potential long term energy futures (e.g., 20-years). WECC is also working to further integrate its PCM, CXM, and power flow model (PFM). The PCM is ideal for learning how efficiently the system may be utilized economically and where weaknesses exist and under what conditions. The PFM is ideal for examining the reliability of the system in greater detail through power flow (PF) analyses which could include contingency analysis,congestion analysis, reactive voltage support, transfer capabilities, and dynamic stability, to name a few. The CXM, using the LTPT, is ideal for gaining an understanding of potential energy futures and what investment decisions might be needed in terms of future generation and transmission infrastructure.