If any public utility, in establishing, constructing, reconstructing, or extending its route, line, plant or system, shall interfere or be about to interfere with the existing route, line, plant, or system of any other public utility, the commission, on complaint of the public utility claiming to be injuriously affected, may, after hearing, make such order and prescribe such terms and conditions in harmony with this part as are just and reasonable. The commission shall have power, after a hearing involving the financial ability and good faith of the applicant, the necessity for additional service in the municipality or territory, and such other matters as it deems relevant, to issue a certificate of public necessity and convenience, or to refuse to issue the same or to issue it for the establishment or construction of a portion only of the contemplated plant, route, line, or system or extension thereof, or for the partial exercise only of such right or privilege, and may attach to the exercise of the rights granted by the certificate such terms and conditions as to time or otherwise as in its judgment the public convenience, necessity, and protection may require, and may forfeit such certificate after issuance, for noncompliance with its terms, or provide therein for an ipso facto forfeiture of the same for failure to exercise the rights granted within the time fixed by the commission; provided, that nothing in this part shall be construed as requiring such certificate for a municipally owned plant, project, or development.