Operational Controls for Balancing Reserves

Limiting Balancing Reserve Deployed or Regulating Reserves Deployed

October 4th, 2024

I. Purpose

During times when BPA is not participating in the Energy Imbalance Market (EIM), Operational Controls for Balancing Reserves (OCBR) will provide directions to limit variable energy resource (VER) plant generation when there are insufficient DEC balancing reserves available to offset over-generation of resources and/or under-consumption by load within the BPA Balancing Authority Area. OCBR also provides instructions about curtailing each plant’s schedules/e-Tags when their actual generation output is less than their scheduled amount. This includes when there are insufficient INC balancing reserves available to offset the under-generation of non-federal VERs and dispatchable energy resources and/or over-consumption by load within the BPA Balancing Authority Area. 

When BPA is participating in the EIM, OCBR provides guidance to limit plant generation when there are insufficient DEC regulating reserves available to offset the over-generation of resources and/or under-consumption by load within the BPA Balancing Authority Area.  Regulating reserves are deployed by the BPA Balancing Authority for the error of generation and load in the Balancing Authority Area versus their EIM market dispatches.  Regulating reserves are never deployed to serve EIM transfers. OCBR pauses the deployment of regulating reserves when there are insufficient INC regulating reserves available to offset the under-generation of non-federal resources and/or over-consumption by load within the BPA Balancing Authority Area.  Regulating Reserves remain paused until the EIM market dispatches relieves the INC regulating reserve deployment.

II. Actions outside of the EIM

BPA calculates the total amount of regulating reserves needed at any given time for all users (Load, Dispatchable Energy Resources and VERs) within BPA’s Balancing Authority. Using this information, BPA takes action when 90% or greater of INC or DEC regulating reserves are deployed from the FCRPS. BPA will establish the amount of regulating reserve capacity available, consistent with and included in the Gen Inputs section of the BPA Rate Case.

A. Procedures for Generation Limitations to Schedule
When BPA is supplying DEC balancing reserves over 90%, BPA requires generators to pause or reduce generation. BPA Dispatchers will send generation targets and notifications to each variable generator through BPA’s Automatic Generation Control (AGC) system. An external BPA web application, called iCRS Generation Advisor, is available with additional information and graphical presentation to supplement the signals sent directly to the plants.  Changes must be made by plants within 10 minutes of receiving electronic directives from BPA. The Limitation remains in effect for the remainder of the hour for events that occur prior to XX:45 and in effect through the next operating hour for events that occur at XX:45 or later.  A plant’s failure to comply with Dispatchers directives may result in penalties as determined in BPA’s Failure to Comply Business Practice.

B. Procedures for Curtailing Schedules to Generation
When BPA is supplying INC balancing reserves in excess of 90%, BPA automatically curtails transmission schedules for each non-federal plant that is under generating. This is accomplished through the existing NERC e-Tagging system with a curtailment reason of “OCBR – Exceeding Reserve Threshold”.

III. Actions in the EIM

BPA calculates the total amount of regulating reserves needed at any given time for all users (Load, Dispatchable Energy Resources and VERs) within BPA’s Balancing Authority. Using this information, BPA takes action when 90% or greater of INC or DEC regulating reserves are deployed from the FCRPS. BPA will establish the amount of regulating reserve capacity available, consistent with and included in the Gen Inputs section of the BPA Rate Case.

A. Procedures for Generation Limitations to Schedule
When BPA is supplying DEC regulating reserves in excess of 90%, BPA requires VER generators to pause or reduce generation. BPA Dispatchers will send generation targets and notifications to each variable generator through BPA’s AGC system.  An external BPA web application, called iCRS Generation Advisor, is available with additional information and graphical presentation to supplement the signals sent directly to the plants. Changes must be made by plants within 10 minutes of receiving electronic directives from BPA. The Limitation remains in effect for approximately 35 minutes with the limitation being relaxed across the last 20 minutes of the event. Events may retrigger during the duration of the event.  A plant’s failure to comply with Dispatcher directives may result in penalties as determined in BPA’s Failure to Comply Business Practice.

B. Procedures for Under-Generation Events
When BPA is supplying INC regulating reserves in above 95%, BPA will pause deployment of regulating reserves within the bounds of reliability and compliance with NERC standards. BPA will submit Manual Dispatches to the EIM for non-VER resources that are under-generating by 5 MW or more at the time of an OCBR under-generating event. If the under-generation event persists, BPA may request a Load Conformance adjustment from the EIM to address persistent regulating reserve deployment causes by VERs.  OCBR Under-Generation events will typically last a minimum of 45 minutes, though they may end earlier or be extended for persistent deployment of regulating reserves. 

OCBR Related Data

Click here to view OCBR-related historical datasets. Historical Generation and Load data can be found under number five, “Data for BPA Balancing Authority Total Load, Wind Gen, Wind Forecast, Hydro, Thermal, and Net Interchange”. Historical BPA EIM status, Balancing Reserves Deployed and OCBR state data can be found under number twelve, “Data for BPA Balancing Reserves Deployed and BPA State(s)”.

Request Forms

Applicant Access Request form 

Security Officer Access Request form 

Automatic Generation Control

AGC Letter (07/24/2024)

Historical Documents

BPA Clarifications on the DSO 216 Assessment of Strikes (2/25/2015)  

DSO 216 Phase II Summary (12/13/2013)

DSO 216 Operational Controls for Balancing Resources (12/13/2013)

DSO 216 Operational Controls Operations & Requirements (12/13/2013)

Connecting Variable Generating Resources (7/2/2010)  

Related Links

November 5, 2020 and November 19, 2020 presentations: Upcoming iCRS Changes  

Netting Resources Business Practice

Failure to Comply Business Practice