Exhibit 99.1 (F)



                           Jones, Day, Reavis & Pogue
                                 77 West Wacker
                                   Suite 3500
                             Chicago, Illinois 60601
                                  312-782-3939

                                  June 4, 2002


Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C. 20549

Re:  Exelon Corporation SEC File No. 70-10003

Ladies and Gentlemen:

We refer to the Application-Declaration on Form U-1 in File No. 70-10003, as
amended (the "Application"), under the Public Utility Holding Company Act of
1935, as amended (the "Act"), filed by PECO Energy Company ("PECO"), a
Pennsylvania corporation and a utility subsidiary of Exelon Corporation, a
registered holding company under the Act, and authorized by order of the
Commission dated December 27, 2001 (the "Order") granting authority under
Section 13 of the Act for PECO to provide certain services to PECO Energy
Transition Trust ("PETT") at a price other than cost as defined in Commission
rules pursuant to an Amended and Restated Master Servicing Agreement, dated
March 25, 1999, as amended; all as more fully described in the Application and
the Order.

         We have acted as counsel to Exelon, PECO and PETT in connection with
the filing of the Application. All capitalized terms used herein but not defined
herein shall have the meaning ascribed to them in the Application.

         In connection with this opinion, we have examined the Application and
the Servicing Agreement, and originals, or copies certified to our satisfaction,
of such corporate records of Exelon, PECO and PETT, certificates of public
officials, orders of regulatory bodies having jurisdiction over aspects of the
Transaction, certificates of officers and representatives of PECO and PETT and
such other documents, records and matters of law as we have deemed necessary for
the purposes of this opinion.

         Based on the foregoing, and subject to the assumptions, qualifications
and limitations hereinafter specified, we are of the opinion that:

         1.    The laws of the State of Pennsylvania applicable to the
               Transaction have been complied with.




         2.    The consummation of the Transaction does not violate the legal
               rights of the lawful holders of any securities issued by PECO,
               PETT or any associate company of either of them.

         The opinions expressed above in respect of the Transaction as described
in the Application are subject to the following assumptions or conditions:

               a.   The authorizations and approvals of the Transaction given by
                    the Board of Directors of PECO and the appropriate approvals
                    of PETT were in effect at the closing thereof.

               b.   The Transaction was accomplished in accordance with required
                    approvals, authorizations, consents, certificates and orders
                    of all state and federal commissions or regulatory
                    authorities having jurisdiction over the Transaction
                    (including the approval of the Pennsylvania Public Service
                    Commission under the applicable laws of the Commonwealth of
                    Pennsylvania) and all such required approvals,
                    authorizations, consents, certificates, orders and
                    registrations remained in effect at the closing thereof.

               c.   We have assumed the genuineness of all signatures and the
                    authenticity of all documents submitted to us as originals
                    and the conformity with the originals of all documents
                    submitted to us as copies. As to various questions of fact
                    material to such opinions we have, when relevant facts were
                    not independently established, relied upon certificates by
                    officers of PECO and other appropriate persons and
                    statements contained in the Application.

         We hereby consent to the filing of this opinion as an exhibit to the
Application.

                                                      Respectfully yours,

                                                      Jones, Day, Reavis & Pogue

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