This excerpt taken from the PCG 10-K filed Feb 18, 2005.
Transmission Owner Rate Cases
Under the FERC's regulatory regime, the Utility is able to file a new base transmission rate case under the Utility's transmission owner tariff whenever the Utility deems it necessary to increase its rates within certain guidelines set forth by the FERC. The Utility is typically able to charge new rates, subject to refund, before the outcome of the FERC ratemaking review process.
The Utility's transmission owner tariff includes two rate components:
The Utility derives the majority of the Utility's transmission revenue from base transmission rates.