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                                                                    EXHIBIT 99.5

                  Consent of Morgan Stanley & Co. Incorporated

    We hereby consent to the use in the Registration Statement of Exelon
Corporation on Form S-4 and in the Joint Proxy Statement/Prospectus of Exelon
Corporation and Public Service Enterprise Group Incorporated, which is part of
the Registration Statement, of our opinion dated December 20, 2004 appearing as
Annex D to such Joint Proxy Statement/Prospectus, and to the description of such
opinion and to the references to our name contained therein under the headings
"Summary--PSEG's Financial Advisor Delivered its Opinion to the PSEG Board of
Directors to the Effect that, as of December 20, 2004, the Exchange Ratio Under
the Merger Agreement Was Fair, from a Financial Point of View, to the Holders of
PSEG Common Stock," "The Merger--Background," "The Merger--Recommendation of the
PSEG Board; PSEG's Reasons for the Merger" and "The Merger--Opinion of Financial
Advisors--Opinion of PSEG's Financial Advisor." In giving the foregoing consent,
we do not admit that we come within the category of persons whose consent is
required under Section 7 of the Securities Act of 1933, as amended (the
"Securities Act"), or the rules and regulations promulgated thereunder, nor do
we admit that we are experts with respect to any part of such Registration
Statement within the meaning of the term "experts" as used in the Securities Act
or the rules and regulations promulgated thereunder.

                                          MORGAN STANLEY & CO. INCORPORATED

                                          By: /s/ J. Perry Offutt
                                             ------------------------------

New York, New York
April 14, 2005