Does the California Energy Commission have the power to prevent utilities from resorting to accounting practices resulting in unreasonably inflated expense figures?

The commission attempts to rely upon language in City and County of San Francisco v. Public Utilities Com., (1971), 6 Cal.3d 119, 98 Cal.Rptr. 286, 490 P.2d 798 to the effect that it has the power to prevent utilities from resorting to accounting practices resulting in unreasonably inflated expense figures and may disallow expenditures reflecting unreasonable costs for materials. However, that case was concerned with the calculation of future costs for the purpose of fixing future rates not for [20 Cal.3d 839] calculating past lawful profits for the purpose of refunds or credits against future rates. (6 Cal.3d at pp. 126-129, 98 Cal.Rptr. 286, 490 P.2d 798.)