II. Background - Gas Tariffs Offer a Range of Services and Levels of Reliability

Currently, PG&E and SoCalGas each have tariffs that determine service priorities in the event of a natural gas curtailment or diversion. The priority of service differs for the customer depending on the service purchased and the specific terms of the utility's tariffs. The rulemaking that initiated this proceeding, R.01-03-023, describes the curtailment priorities of PG&E and those of SoCalGas in great detail which we will not repeat. Under each tariff, all purchasers of noncore gas receive similar treatment in the event of curtailments. On PG&E's system, all noncore end user customers have gas diverted on a pro rata basis when curtailments affect the noncore service category. For SoCalGas, those customers purchasing interruptible intrastate service are interrupted according to the "percentage of default rate" that they pay, with customers who pay the lowest "percentage of default rate" curtailed first.

Under the tariffs of PG&E and SoCalGas, those who purchase and store gas can obtain gas even without access to "flowing gas." PG&E's tariff states that "scheduled deliveries from storage using Firm or As Available transmission services will be treated as the highest priority Firm service." For SoCalGas, a "firm unbundled storage withdrawal" receives a higher dispatch priority than either interruptible or firm service. Thus, withdrawals from storage enable noncore gas customers to ensure their access to gas even when flowing gas supplies prove inadequate.