BILLING.

(a) A gas utility or municipally owned utility may not bill or otherwise require the state or a state agency or institution to pay for service before the service is provided. (b) The railroad commission shall adopt rules concerning payment of bills by the state or a state agency to a gas utility or municipally owned utility. The rules must be consistent with Chapter 2251, Government Code. (c) This subtitle does not prohibit a gas utility or municipally owned utility from entering into an agreement with the state or a state agency to establish a level or average monthly service billing plan. An agreement under this subsection must require reconciliation of the leveled or equalized bills quarterly.