QuickLinks -- Click here to rapidly navigate through this document

File No.                     

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C.
FORM U-57
NOTIFICATION OF FOREIGN UTILITY COMPANY STATUS
Filed under section 33(a) of the
Public Utility Holding Company Act of 1935, as amended

AES Barka SAOC
(Name of foreign utility company)

THE AES CORPORATION
1001 N. 19th Street
Suite 2000
Arlington, Virginia 22209
(Name of filing company, if filed on behalf of foreign utility company)

The Commission is requested to mail copies of all correspondence relating to this Notification to:

Ashley A. Meise
The AES Corporation
1001 N. 19th Street
Suite 2000
Arlington, Virginia 22209


Andrew B. Young
Hugh E. Hilliard
Dewey Ballantine LLP
1775 Pennsylvania Avenue, N.W.
Washington, D.C. 20006

ITEM 1

        Foreign utility status is claimed by AES Barka SAOC ("AES Barka"), a closed joint stock company organized under the laws of Oman, with its business address at P.O. Box 572, Barka, Postal Code 320, in the Sultanate of Oman.

        AES Barka owns and operates a natural gas-fired, combined cycle power generation and desalination facility located in Barka, Oman, which is capable of supplying approximately 427 MW of electric energy and 20 million gallons per day of water.

        The AES Corporation ("AES") indirectly owns approximately 85% of the voting interests in AES Barka. The remaining 15% of the voting interests is owned by Multitech LLP ("Multitech").

        AES, a Delaware corporation, is a public utility holding company exempt from registration under section 3(a)(5) of the Public Utility Holding Company Act of 1935 (the "Act"). The AES Corp., Holding Company Act Release No. 27363 (Mar. 23, 2001). Multitech is organized under the laws of Oman.

ITEM 2

        AES Barka has one domestic associate public utility company, Indianapolis Power and Light Company ("IPL"). IPL is wholly owned by IPALCO Enterprises Inc., which, in turn, is a wholly-owned subsidiary of AES. IPL has not made any investment in, nor has any contractual relationship with, AES Barka, nor are any such investments or contractual relationships contemplated.

EXHIBIT A

        By letter dated September 28, 2000, the Indiana Utility Regulatory Commission certified to the Securities and Exchange Commission with respect to IPL that (1) it has the authority and resources to protect ratepayers subject to its jurisdiction, and (2) it intends to exercise that authority as required under section 33(a)(2) of the Act in connection with AES' acquisition of foreign utility companies. AES hereby incorporates this letter, filed October 27, 2000, in file number 070-09779, by reference.

        The undersigned company has duly caused this statement to be signed on its behalf by the undersigned thereunto duly authorized.

By: /s/  ASHLEY A. MEISE Ashley A. Meise
Assistant General Counsel
The AES Corporation
1001 N. 19th Street, Suite 2000
Arlington, Virginia 22209
(703) 292-0817

Dated: December 1, 2003

QuickLinks

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. FORM U-57 NOTIFICATION OF FOREIGN UTILITY COMPANY STATUS Filed under section 33(a) of the Public Utility Holding Company Act of 1935, as amended