Transmission Cost Adjustor

What is the Transmission Cost Adjustor (TCA)?

The TCA is a charge or credit that reflects a portion of transmission costs associated with serving retail electric customers.

TEP’s modern energy grid spans 1,155 square miles and includes more than 2,000 miles of transmission lines. Since 2018, TEP invested more than $148 million in improvements to its transmission system.

Why does TEP need a TCA?

The TCA provides timely price adjustments - either up or down - related to the cost of providing transmission service to retail customers.

How is this calculated?

TEP calculates this amount annually based on investments in its transmission system using a formula approved by the Federal Energy Regulatory Commission (FERC), subject to review and approval by the Arizona Corporation Commission (ACC).

How does this affect my bill?

For residential customers, the current TCA rate is set as a credit of $0.000830 per kWh, which results in a bill credit of more than 60 cents for a residential customer with average monthly usage of about 800 kWh.

Where does the TCA appear on my bill?

The TCA appears under Delivery Charges.

Do other utilities have charges like this?

Yes. The ACC has approved similar TCA mechanisms for Arizona Public Service (APS) and UniSource Energy Services.