Said City shall have power, within and without its territorial limits, to construct, condemn, purchase, acquire, lease, improve, add to, maintain and conduct and operate in whole or in part, water works, water pipelines and pump stations, light plants, telephone systems, power plants, transportation systems, heating plants, incinerating plants and disposal plants, sanitary sewers, storm sewers and drains, and any other public utility or works or ways, and everything required therefore. And any such systems, plants, works, or ways or any contracts in relation or connection therewith that may exist and which said City may desire to purchase in whole or in part maybe purchased or acquired, in whole or in part, by said City which may enforce said purchase by proceeding at law or in equity or by right of eminent domain, said City shall have the power to issue bonds upon the vote of the tax paying electors at any special or general election in any amount necessary to carry out any of said powers or purposes, said amount being alone limited by the Constitution of the State of Oklahoma. Provided, however, that the power to condemn shall not be exercised for the purpose of acquiring such utilities now existing and operating under franchise granted by a vote of the people except under the terms of said franchise. Provided, further, that the same exemption from the power to condemn may be embodied in any franchise for any other public service or public utility corporation that may be hereafter submitted to a vote of the people.