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Exhibit 23

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in the Registration Statements on Form S-3 and Form S-8 (Nos. 333-102723, 333-59601, 33-57658, 333-56572, 333-24705, and 33-49801, and 33-59545, 333-45051, 333-46980, 333-89046, 333-81292 and 33-56084, respectively) of Constellation Energy Group, Inc. of our report dated March 10, 2005 relating to the financial statements, financial statement schedule, management's assessment of the effectiveness of internal control over financial reporting and the effectiveness of internal control over financial reporting, which appears in this Form 10-K.

PRICEWATERHOUSECOOPERS LLP

Atlanta, Georgia
March 11, 2005

We hereby consent to the incorporation by reference in the Registration Statements on Form S-3 (No. 333-102432) of Baltimore Gas and Electric Company of our report dated March 10, 2005 relating to the financial statements and financial statement schedule, which appear in this Form 10-K.

PRICEWATERHOUSECOOPERS LLP

Atlanta, Georgia
March 11, 2005

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CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM