A more accurate picture of the grid means more transmission service for customers.
Tucson Electric Power has moved its available transfer capability (ATC) calculation from Rated System Path to the Flowgate methodology, and Utilicast is proud to have served as system integrator for the transition.
Rated System Path treats transfer capability as a fixed number on a contract path. The Flowgate approach calculates capability against the constraints that actually limit flow. That reflects how power really moves across an interconnected Western grid, and it lets the utility post ATC that matches physical reality instead of a conservative approximation. The result is additional transmission service capability that would otherwise sit unused.
The work went well beyond software configuration:
- An up-front assessment of cost and effort against NAESB requirements, before a dollar was committed to the change
- Configuration and data integration of vendor software, including the models and data flows feeding them
- The process, role, and business-practice changes needed to operate the methodology every day
- Coordination with utilities across Arizona and New Mexico to model the Flowgate methodology region-wide
This milestone rests on a relationship that started in 2019. Utilicast served as a system integrator for TEP’s multi-year entry into the CAISO Western Energy Imbalance Market (EIM). Along the way we helped with new EMS, tuned the network model for state estimation and real-time contingency analysis, build PI-based visualization for operators, and supported EIM settlements. We also assessed and supported TEP’s ADMS through its first years of operation. Today we are supporting the utility’s entry into SPP Markets+.
Thank you to Tucson Electric Power for the trust, for the partnership, and for permission to share this work. Congratulations to the joint TEP and Utilicast team that got it done.
