ATC Methodology

This page contains BPA’s ATC methodologies for both the Short-term (0-13 months) and Planning (long-term) horizons and other related information. You can find tools and reports to help evaluate and analyze transmission availability here. 

Effective 10/1/2023, BPA does not calculate ATC for the for the flow-based paths (Map of Long-Term BPA Constraints) in the long-term planning time horizon (beyond 13 months through 10 years).  Commercial powerflow studies are performed to evaluate whether transmission service requests and/or Network Load and resource forecasts, impacting flow-based constraints during this time period, can be granted or require additional study to identify transmission system upgrades necessary to reliably offer transmission service.

Short-term Horizon (0 - 13 months)

ATC Implementation Document, V85 
(Effective 11/27/2024)

ATC Implementation Document Version History
(Effective 11/27/2024) 

TRM Implementation Document, V10
(Effective 02/01/2024)

CBM Implementation Document
(Effective 04/14/2023)

System Operating Limits Methodology for the Operations Horizon

Map of Short-term BPA Constraints
(Effective 02/13/2024)

Data Request Form *
(02/01/2024)

* The Data Request Form is only for use by the specific entities identified in the form. Send all completed forms to nercatcstandards@bpa.gov with "Data Request Form" in the subject line.

Planning Horizon (beyond 13 months)

Firm Available Transfer Capability (ATCF) Methodology for the Long-Term Planning Time Horizon V19
(Effective 10/01/2023)   

Map of Long-term BPA Constraints (Effective 12/15/2023)

Data Exhibit Validation Requirements - Final (Posted 09/03/2024)

Reference Documents

Contact Information

Please send any data-sharing requests or questions about BPA’s TTC/ATC/TRM/CBM methodologies to nercatcstandards@bpa.gov. Please specify the nature of your request in the subject line. For general comments or questions about ATC, email techforum@bpa.gov and specify “ATC-related” in the subject line.

To receive emails about ATC Methodology updates and Customer Involvement meetings, select the techforum mail list check box on the sign-up form.

Related Pages: