Section 775 Of Article 3. Equipment, Practices, And Facilities From California Public Utilities Code >> Division 1. >> Part 1. >> Chapter 4. >> Article 3.

. Whenever an electric or gas corporation sells fuel oil which is, or is reasonably expected to be, useful in the performance of its public utility function, at a price higher than the electric or gas corporation's purchase cost, the commission shall, in any rate proceeding, require that the amount higher than the purchase cost be credited with interest against the expense claimed by the electric or gas corporation.