The public interest requires, and it is declared to be the policy of the State of Georgia, that, in order (1) to assure the most efficient, economical, and orderly rendering of retail electric service within the state, (2) to inhibit duplication of the lines of electric suppliers, (3) to foster the extension and location of electric supplier lines in the manner most compatible with the preservation and enhancement of the state's physical environment, and (4) to protect and conserve lines lawfully constructed by electric suppliers, it is necessary and appropriate that the state establish and implement a plan whereby every geographic area within the state shall be either assigned to an electric supplier or declared unassigned as to any electric supplier; that, to accomplish such a plan, it is necessary that all electric suppliers within the state be subject to this part; that the commission be delegated power, authority, and jurisdiction with respect to such plan; and that all electric membership corporations and all municipalities which furnish retail electric service be additionally subject to regulation by the commission in the same manner as provided for regulation of electric light and power companies, except as to the fixing of their rates, charges, and service rules and regulations, it being determined by the General Assembly that such electric membership corporations and municipalities, which by their corporate nature are wholly or substantially controlled by their consumers, should for regulatory purposes be classified differently in certain respects from electric light and power companies.