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    <Log type="Info">'Monetary' elements on report '4133 - Disclosure - Derivatives and Fair Value Measurements (Details 4)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '4160 - Disclosure - Related Party Transactions (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">Process Flow-Through: 0010 - Statement - CONSOLIDATED STATEMENTS OF INCOME (LOSS) (Constellation Energy Group, Inc. and Subsidiaries)</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Dec. 31, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Jun. 30, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '9 Months Ended
Sep. 30, 2011'</Log>
    <Log type="Info">Process Flow-Through: 0020 - Statement - CONSOLIDATED BALANCE SHEETS (Constellation Energy Group, Inc. and Subsidiaries)</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2009'</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2008'</Log>
    <Log type="Info">Process Flow-Through: 0025 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical) (Constellation Energy Group, Inc. and Subsidiaries)</Log>
    <Log type="Info">Process Flow-Through: 0030 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS (Constellation Energy Group, Inc. and Subsidiaries)</Log>
    <Log type="Info">Process Flow-Through: 0045 - Statement - CONSOLIDATED STATEMENTS OF COMMON SHAREHOLDERS' EQUITY AND COMPREHENSIVE INCOME (LOSS) (Parenthetical) (Constellation Energy Group, Inc. and Subsidiaries)</Log>
    <Log type="Info">Process Flow-Through: 0050 - Statement - CONSOLIDATED STATEMENTS OF INCOME (Baltimore Gas and Electric Company)</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Dec. 31, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Sep. 30, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Jun. 30, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Mar. 31, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Dec. 31, 2010'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Sep. 30, 2010'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Jun. 30, 2010'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Mar. 31, 2010'</Log>
    <Log type="Info">Process Flow-Through: 0060 - Statement - CONSOLIDATED BALANCE SHEETS (Baltimore Gas and Electric Company)</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2009'</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2008'</Log>
    <Log type="Info">Process Flow-Through: 0065 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical) (Baltimore Gas and Electric Company)</Log>
    <Log type="Info">Process Flow-Through: 0070 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS (Baltimore Gas and Electric Company)</Log>
  </Logs>
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    <File>ceg-20111231.xml</File>
    <File>ceg-20111231.xsd</File>
    <File>ceg-20111231_cal.xml</File>
    <File>ceg-20111231_def.xml</File>
    <File>ceg-20111231_lab.xml</File>
    <File>ceg-20111231_pre.xml</File>
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</FilingSummary>
