EIM Ancilliary Services

Capacity on the FCRPS is set aside for use to cover deviation in actual load from the loads schedule.

Schedule 4e (EIM): Energy Imbalance (the energy side of Schedule 3)

  • Energy Imbalance Service is provided when a difference occurs between the scheduled and the actual delivery of energy to a load located within a Control Area over a scheduling period. The Transmission Provider must offer this service when the transmission service is used to serve load within its BAA. The Transmission Customer must either purchase this service from the Transmission Provider or make alternative comparable arrangements, which may include use of non-generation resources capable of providing this service, to satisfy its Energy Imbalance Service obligation. To the extent the BAA operator performs this service for the Transmission Provider, charges to the Transmission Customer are to reflect only a pass-through of the costs charged to the Transmission Provider by that Control Area operator.
  • See the Transmission Rates webpage for the latest Ancillary Services Rates.
    • Charge for Capacity (Schedule 3)
    • Charge/Credit for Energy (Schedule 4)
  • Related Business Practices
    • Energy Imbalance Service BP (exposure to persistent deviation)
    • EIM BP

Schedule 9e (EIM): Generation Imbalance

Generation Imbalance is: BPA as the Balancing Authority, is responsible for ensuring that Generation = Load in accordance with regional (WECC) and national (NERC) reliability standards.  
  • BPA utilizes generation inputs to provide Ancillary and Control Area Services to maintain load-resource balance at all times and to respond to the many variables that affect transmission system reliability in its BAA. 
  • Generation inputs are the various uses of generation resources that are needed by BPA in order to provide Ancillary Services, Control Area Services, and other services that are necessary to support reliable operations of the transmission system. 
  • See the Transmission Rates webpage for the latest Ancillary Services Rates.
  • Related Business Practices