Rev. & Tax. Code, § 40111

(a) If the department determines that any amount, penalty, or interest has been paid more than once or has been erroneously or illegally collected or computed, the department shall set forth that fact in the records of the department, certify the amount collected in excess of the amount legally due and the person from whom it was collected or by whom paid, and shall credit the excess amount collected or paid on any amounts then due and payable from the person from whom the excess amount was collected or by whom it was paid under this part, and the balance shall be refunded to the person, or the person’s successors, administrators, or executors. Any determination by the department pursuant to this section with respect to an amount in excess of fifty thousand dollars ($50,000) shall be available as a public record for at least 10 days after the effective date of that determination.

(b) Any overpayment of the surcharge by a consumer to the state shall be credited or refunded by the state to the consumer.

(c) (1) Except as provided in paragraph (2), any overpayment of the surcharge by the consumer to an electric utility that is required to collect the surcharge shall be refunded by the state to the consumer.

(2) If the electric utility has paid the amount to the department and establishes to the satisfaction of the department that it has not collected the amount from the consumer or has refunded the amount to the consumer, the overpayment may be credited or refunded by the state to the electric utility.