Northwest Power Pool Processes

Transcription

1 Northwest Power Pool Processes Background The Northwest Power Pool membership (NWPP) was founded in 1941 to promote efficient production of electrical energy. The NWPP is the geographic area encompassed by the electric systems of the NWPP Agreement Signatories. This area includes the states of Washington, Oregon, Idaho, Montana, Utah, and Wyoming; portions of northern California and northern Nevada; and the Canadian provinces of British Columbia and Alberta. The NWPP is a collective voice for the coordination of operating reliability issues, addressing both adequacy and transmission reliability for consumers within the area. The NWPP, as well as NERC and the WECC, set reliability criteria and policies for the entities within their respective areas. The NWPP participants implement these criteria and policies in a coordinated and collective manner. The NWPP committees have a long-standing history of cooperatively working together to address problems. They are also forums to coordinate the operation and planning of the area s bulk electric system. It is within these committees that detailed discussion and debate results in the NWPP programs related to the reliable operation and planning of the area s hydro/thermal resources and interconnected transmission grid. Under the guidance of the NWPP, the area s entities have developed regional reliability processes and procedures to assure interconnected system reliability through regional coordination. These processes and procedures have been extremely effective in maintaining coordination, communications, and system reliability. The NERC Reliability Standards and requirements explicitly state that the Reliability Coordinator (RC) is now ultimately responsible for some of these regional processes and procedures. The RC can delegate these functions to other entities but must maintain the responsibility to comply with the standards and requirements. The NWPP consists of twenty balancing authorities which are obligated to comply with any Peak RC requested directive(s). This document describes the NWPP area s processes and procedures that are in place and have been effective in maintaining system reliability. The operating reliability processes include: coordinated (transmission) outage processes, seasonal evaluation of transmission constraints and system operating limits (SOL), next day reliability analysis, automated contingency reserve sharing, coordinated under-frequency load shedding programs, coordinated under-voltage load shedding programs, power and reactive sign conventions, energy emergency plan, interconnection clearance and hold terminology, and coordinated communication during critical operating conditions. The planning processes include: Coordinated hydro planning, drought coordination planning, transmission expansion, area coordination, transmission adequacy, and long-range significant outage planning.

2 The following information summarizes the existing NWPP process and procedures. Individual Balancing Authorities (BA), Transmission Operators (TO), and Peak RC can use this information as documentation for future NERC Readiness Audits and FM certifications. Operating Processes Outage Coordination The NWPP coordinated outage (transmission) system) was designed to assure that outages could be coordinated among all stakeholders (operators, maintenance personnel, transmission users, and operations planners) in an open process. This process had to assure that proper operating studies were accomplished and transmission impacts and limits known, to fulfill a requirement from the 1996 west coast disturbances that the system be operated only under studied conditions. The RC is involved in the outage coordination process and has direct access to the outage data base. Monthly Coordination The process requires NWPP members to designate significant facilities that if out of service by itself or in conjunction with another outage, will impact system capabilities. The significant facilities are defined and updated annually by the NWPP members. The scheduled outage of these critical facilities is posted on a common database. All utilities post proposed significant outages on Peak RC s Coordinated Outages System (COS). Outages are to be submitted to the COS at least 45 days ahead of the month they are proposed to occur so they can be viewed by interested entities. The involved entities then facilitate the NWPP coordination of all these outages. Entities can comment on the preliminary impacts and schedules may be adjusted to maximize reliability and minimize market impacts. If coincidental outages cause too severe of an impact, the requesting utilities work together to adjust schedules accordingly. Priority is given to the outages that were posted first, taking into account comments received from interested parties with each transmission operator making decisions for their lines. A final outage plan is posted with estimated path capabilities 30 days prior to the month in which the outages will occur. Detailed operational transfer capability studies are then performed and the limits for each affected path are posted at least 15 days prior to the outage. Emergency outages can be requested outside these schedule guidelines. Emergency outages are coordinated among adjacent utilities to minimize system exposure. Utilities can use the COS system to ensure system topology is correct for next day studies. As transmission operators increase the amount of short term outages in addition to the significant outages, the Peak RC will be able to use the final outage schedule in its real-time system analysis. This coordinated outage process has been very effective. The outage information is used by NWPP member utilities to perform system studies to maximize system reliability.

3 Semi-annual planning - Long-Range Significant Outage Planning (LRSOP) The NWPP staff facilitates outage meetings every six months with each utilities outage coordinator to discuss proposed longer term outages. Utilities discuss anticipated outages needed for time critical construction and periods where transmission capacity may need to be maximized. The outages are posted on the Peak RC COS and on the individual companies OASIS sites. Specific responsibilities of LRSOP include: Share outage information with all parties affected by outages of significant equipment (i.e. equipment that affects the transfer capability of rated paths). Information is shared two times each year for a minimum of a six-month period. The first meeting each year coordinates outages for July through December. The second meeting coordinates outages for January through June. Review the outage schedules to insure that needed outages can be reliably accomplished with minimal impact on critical transmission use. Outage coordinators are to post the outages on the Coordinated Outages System within the applicable timeframes. Northwest Operation and Planning Study Group A recommendation of the 1996 west coast disturbances was the requirement to not operate in conditions that have not been studied. This requirement, lead to the formalization of a study and review process to determine seasonal operating transfer capability (OTC) also known as system operating limits (SOL) limits for critical paths in WECC. The NWPP entities had, through a cooperative working relationship, shared information prior to the formalization of the process. The initial focus for this effort was the California-Oregon Intertie (COI) because this path was involved in both 1996 disturbances. The seasonal study process was eventually expanded from the COI to all WECC paths listed in the WECC path rating catalog. The WECC created the Operating Transfer Capability Policy Committee (OTCPC) and corresponding SOL study and review process. This process divided the WECC into regional study groups that are responsible to perform and approve seasonal studies on significant paths in their region to determine the maximum SOL. The NWPP formalized the Northwest Operation and Planning Study Group (NOPSG), which is composed of the path operators and/or owners of critical NW transmission paths and any other interested NWPP members. The results of NOPSG seasonal studies and SOLs are provided by the respective Tops to the Peak RC. The NOPSG process is available on the NWPP website in the Operating Committee area and Transmission Planning Committee area.

4 Next Day Operating Studies Additional path curtailments may be required depending upon current system conditions and outages. These curtailment studies are performed by the individual path operators based on the outage schedule developed through the COS process. According to the COS process, these studies are performed at least 15 days prior to the outage. Individual path operators and transmission owners may also perform updated next day studies to capture emergency outage requests and current system conditions such as generation dispatch to determine if the SOL studies and limits are still accurate. Based on these studies, additional SOL curtailments may be made by the path operators. The modified SOL s are posted on the individual transmission owners OASIS and the Peak RC is notified. The Peak RC also performs system studies to ensure interconnected system reliability. The Peak RC performs real-time system thermal studies to evaluate current operating conditions across the entire Interconnection. The Peak RC is in the process of incorporating real-time voltage tools to complement the thermal analysis currently being performed. Transient stability analysis capability is planned in the future. When the Peak RC observes real-time reliability problems they contact the path operator to discuss the issue and work on a solution. The Peak RC will make a directive for action if there is an imminent reliability threat and the balancing authority does not eliminate the reliability issue within an appropriate time frame. Contingency Reserve Sharing Procedure As permitted by NERC and WECC criteria and standards, the Operating Committee of the NWPP has instituted a Reserve Sharing Program for contingency reserve and established a permanent committee, the Reserve Sharing Group (RSG) Committee to oversee the Reserve Sharing Program. Those who participate in a RSG are better positioned to meet the NERC disturbance control standard because they have access to a deeper and more diverse pool of shared reserve resources. Also, an increase in efficiency is obtained since the shared reserve obligation for the group as a whole is less than the sum of each participant s reserve obligation computed separately. By sharing contingency reserve, the participants are entitled to use not only their own internal reserve resources, but to call on other participants for assistance if internal reserve does not fully cover a contingency. The reserve sharing process for the NWPP has been automated. A manual backup process is in place if communication links are down or the computer system for reserve sharing is not functioning correctly. The NWPP is designated as a reserve sharing group (RSG) as provided under WECC Operating Reliability Criteria. Each member of the RSG is required to maintained its allocated share of the NWPP RSG s contingency reserve obligation (CRO) or the most severe single contingency (MSSC) whichever is greater. The combined allocated share of the members CRO must be larger than the RSG MSSC. If not, then each allocated share of the member s CRO is proportionally increased until this requirement is met. When any RSG member loses generation they have the right to

5 request assistance reserves from the other RSG members as long as they have first committed their allocated share CRO. A request is sent via the member s energy management system to the central computer. The computer then distributes the request proportionally among members within the RSG. Each member may be called to provide reserve up to its allocated share of the CRO. Critical transmission paths are monitored in this process to ensure SOL limits are not exceeded. If a transmission path SOL is exceeded the automated program redistributes the request among RSG members that are delivering reserve along non-congested paths. Settlement for energy delivered under the reserve sharing program can either be settled financially based on the Powerdex hourly Mid-C market index or by return of like energy. If a reserve request fails due to various reasons, backup procedures are in place to fully address the requirements. Coordinated Underfrequency Load Shedding (UFLS) programs Following the 1996 west coast disturbances, The WECC implemented a west-wide coordinated off-nominal frequency load shedding and restoration plan (the Plan). The Plan consist of three micro plans, one is the he NWPP coordinated the UFLS program for the NWPP area. The NWPP UFLS program is designed to arrest frequency that may result in an uncontrolled failure of components of the Western s Interconnection (WI). The program is coordinated with all areas of the WI to prevent unbalanced load shedding which may result in high transmission loading and extreme voltage deviations. In addition, the plan is designed to protect generating equipment and transmission facilities against damage and leave the system in a condition to permit rapid restoration. Through the WECC UFLS Review Group, the NWPP entities annually review the effectiveness of the design, implementation, and documentation of the UFLS program, and make any necessary changes based on current system conditions. Dynamic planning models are used to determine the effectiveness of the UFLS plan. Voltage Issues Work Group (VI) The VI work group membership is open to all NWPP Operating Committee (OC) members. Specific responsibilities of VI work group include: Facilitate the process to address voltage issues across multiple balancing authorities within the NWPP. Participate in studies to determine impacts of voltage issues and develop guidelines to resolve the problem. Develop and publish methodology and final reports Power and Reactive Sign Conventions The lack of a common standard for metering sign conventions may lead to confusion, which may cause multiple sites to follow opposing conventions. The NWPP has developed a document that provides for a common standard from which to base designs, installations, and written contracts.

6 Energy Emergency Plan (EEP) The overarching purpose of the EEP is to increase the area's ability to avoid a power emergency or longer-term adequacy problem by promoting area coordination and communications. The EEP is aimed at promoting actions, in advance, to avoid potential short-term emergencies and longer-term energy adequacy problems in the NWPP area. These actions are targeted to alleviate the need for the Reliability Coordinator to declare a NERC Energy Emergency Alert level 1, 2, or 3 as defined in NERC Reliability Standard. The EEP is designed to be invoked when the area has a high degree of confidence that a future short-term power emergency or a long-term energy adequacy problem would adversely affect reliability within the NWPP. The EEP is not intended to supplant any entity's authority, but rather it provides the framework for how the utilities, governmental agencies, and other entities will work together should an emergency situation be anticipated as a result of severe weather conditions and/or unexpected outages of transmission or generating facilities that impact load-resource balance. The EEP focuses on area actions and is intended to work with and complement current governmental regulations and policies in place for individual balancing authorities and load serving entities. The intended audience for the EEP is operating entities, near-term planners, and policy makers in the electric power industry as well as the area's governments. It provides objectively defined criteria for communicating emergency warnings and warnings of longer-term area energy adequacy problems within the area that are based on analysis of the load and resource situation. The EEP identifies generic area actions when these warnings are declared, describes the roles and responsibilities of the parties involved, and lays out a communication plan for keeping all stakeholders informed throughout the potential crisis. It is expected that individual entities will use the EEP as a procedural framework for identifying the individual actions they will be able to take when either warnings of power emergencies or warnings of energy adequacy problems are declared. Interconnection Clearance and Hold Terminology The NWPP Operating Committee determined that a common terminology is desirable when Clearances or Holds are required on equipment interconnecting two or more utilities. The NWPP Terminal Clearance assures the requesting Grid Operator/Dispatcher that the terminal or source is open, properly cleared and tagged according to local procedures, and that it will not be energized until a release is given by the Grid Operator/Dispatcher receiving the Terminal Clearance. The NWPP Terminal Hold assures the requesting Grid Operator/Dispatcher that the terminal or source on "hold" has relays in service to provide protection in the event of a fault; and, once tripped out of service, will not be re-energized, automatically or

7 manually, until the Grid Operator/Dispatcher receiving the Terminal Hold has advised that all personnel and materials are in the clear and it is safe to energize. Coordinated Communication during Critical Operating Conditions Entities responsible for operating the bulk electric system within the Northwest Power Pool (NWPP) area have dealt with various conditions over the last few decades. During these times, the Northwest electric industry s expertise, communication, coordination, and cooperation are unique and have served this area and its consumers well. The elements of the NWPP s plan to handle coordinated communications incorporate the following elements: New U.S. Federal Energy Regulatory Commission regulations are in place that enhance market competition, but restrict the ways in which the various elements of our industry may communicate. The Peak RC is staffed to conduct a wide area view and therefore increase the vision, awareness, and effectiveness of balancing authority operators, especially during times of duress. Reliability Standards and procedures have been adopted by North American Electric Reliability Council (NERC) to mitigate and communicate reliability problems, including Energy Emergencies. Coordinated communications provide support to the NWPP entities with respect to public communications during critical operating conditions. Coordinated communications may include, but are not limited to the following: 1) Facilitating meetings of the communications support team, 2) Acting as a liaison between the communications support team and other parties, 3) Representing the NWPP area s entities in public communications and the media, and 4) Providing talking points and other communication aids to the NWPP entities and area policy-makers. Planning Processes Coordinated Hydro Planning The 1997 Pacific Northwest Coordinating Agreement (97 PNCA) requires the development of an annual plan for the coordinated operations of the Coordinated hydroelectric systems as defined by the 97 PNCA. By factoring in weather, river flows and water needed for fish spills, the Coordinating Group s (CG) annual plan estimates how much power will be generated by the Coordinated System s

8 hydroelectric facilities and helps the CG plan for any shortfall. Through this work the NWPP is able to provide seasonal forecast of the area s power requirements and determine whether there will be enough power generated to meet those needs. Drought Coordination Planning Through the CG a forum exists to develop plans to address the area s power requirements under drought conditions and formulate plans to assure power is generated to meet the area s requirements. Transmission Expansion Planning Serve as Forum for open discussion. Develop guidelines for assessing the reliability and efficient development of the transmission system in the NWPP area. Collection and coordination of member s data. Seasonal Assessment. Support underfrequency load shedding simulations. Summary The NWPP Agreements, and any Procedures, Process, Plans, Charters, and Reports sufficiently meet the goal of cooperatively working together to address problems, and the coordination of the reliable operation and planning of the area s bulk electric system. The NWPP documents are reviewed at least annually to assure they meet industry changes and requirements and are available to all NWPP participants committee representatives on the NWPP Website portal Resources section as they relate to each respective Committee.