220 ILCS 30/14
Except as provided in Section 11-117-7.1 of the Illinois Municipal Code and except as otherwise provided in this Section, Sections 5 (other than the first paragraph thereof), 7 and 8 of this Act do not apply to any area which is located within an incorporated municipality on the effective date of this Act and shall cease to apply to any area after it is annexed to or otherwise becomes located within an incorporated municipality. An electric supplier which is serving in an area which has been or hereafter becomes annexed to or otherwise located within an incorporated municipality may continue to furnish service within such annexed or otherwise incorporated area to the premises which it is serving at the time of such annexation or incorporation provided that: (i) no such supplier may extend its lines into any area previously or subsequently annexed or otherwise located within the incorporated municipality in which another electric supplier is authorized to maintain and extend its lines unless in any such case the electric supplier is or shall become authorized to do so by the incorporated municipality and the Commission; (ii) no such supplier serving in an area which has been previously annexed to or otherwise located in an incorporated municipality prior to the effective date of this Act may extend its lines within such annexed or otherwise incorporated area unless in any such case the electric supplier is or shall become authorized to do so by the incorporated municipality and the Commission; and (iii) no such electric supplier which is serving in an area which becomes so annexed to or otherwise located within an incorporated municipality after the effective date of this Act may furnish service to any additional premises or extend its lines into or within such area unless such supplier is or shall become authorized so to do by the incorporated municipality. In making a determination under clause (i) above the Commission shall act in the public interest and shall consider all the factors set forth in Section 8 but shall not be required to give substantial weight to any particular factor and shall take into consideration any applicable certificate of public convenience and necessity. In making a determination under clause (ii) above the Commission shall act in the public interest and shall consider all the factors set forth in Section 8, shall not be required to give substantial weight to any particular factor and shall not take into consideration any certificate of public convenience and necessity.
Nothing in this Section requires any electric supplier to obtain any authorization, either from an incorporated municipality or from the Commission, to extend its lines if, and to the extent that, such supplier, on the effective date of this Act, has such authorization from such municipality or from the Commission under the Public Utilities Act, as the case may be, or as a matter of law, but any such authorization must be lawfully in effect at that time.
Nothing in this Act shall be construed to impair, abridge, or diminish in any way the powers, rights and privileges of incorporated municipalities.
220 ILCS 30/14