The commission, upon its own initiative, may investigate all schedules of rates and rules and regulations of natural gas public utilities. If after investigation and hearing the commission finds that such rates or rules and regulations are unjust, unreasonable, unjustly discriminatory or unduly preferential, the commission shall have the power to establish and order substituted therefor such rates and such rules and regulations as are just and reasonable.

If after investigation and hearing it is found that any regulation, measurement, practice, act or service complained of is unjust, unreasonable, unreasonably inefficient or insufficient, unduly preferential, unjustly discriminatory, or otherwise in violation of this act or of the orders of the commission, or if it is found that any service is inadequate or that any reasonable service cannot be obtained, the commission may substitute therefor such other regulations, measurements, practices, service or acts, and make such order respecting any such changes in such regulations, measurements, practices, service or acts as are just and reasonable. When, in the judgment of the commission, public necessity and convenience require, the commission may establish just and reasonable concentration or other special rates, charges or privileges, but all such rates, charges and privileges shall be open to all users of a like kind of service under similar circumstances and conditions. Hearings shall be conducted in accordance with the provisions of the Kansas administrative procedure act, unless, in the case of a general investigation, for good cause, the commission orders otherwise.