Making the Most of Every Transmission Path


Seattle City Light – Available Transfer Capability (ATC)

Knowing how much additional power can safely flow across the transmission network is fundamental to both grid reliability and efficient energy markets. For Seattle City Light (SCL), Quadrante Right Analytics is developing a robust methodology and calculation process for Available Transfer Capability (ATC): the transfer capability remaining on the network, over and above existing commitments, for further commercial use.

The project builds a complete ATC framework, from refining the system power flow models and defining the transmission paths to be assessed, to calculating Total Transfer Capability (TTC), Existing Transmission Commitments (ETC), Transmission Reliability Margin (TRM) and Capacity Benefit Margin (CBM). Alternative methodologies are evaluated against WECC practice, and the process is implemented in PowerWorld Simulator, using fast linear sensitivity methods to screen hundreds of contingencies efficiently.

Market

USA

Sector

Energy

Services

Engineering

Location

Seattle, Washington, USA

Client

Seattle City Light

An accurate, repeatable ATC process gives utilities a clearer picture of the true capability of their transmission system. Combining rigorous network modeling with efficient computational tools, the project helps Seattle City Light maximize the use of its existing transmission infrastructure, support fair and transparent market access and maintain reliability across its highly interconnected network.