Exhibit No. 12(a)

CONSTELLATION ENERGY GROUP, INC. AND SUBSIDIARIES

COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES

|                                                                                                                         |                                                                                        | 12 Months Ended
|------------------------------------------------------------------------------------------------------------------------ | -------------------------------------------------------------------------------------- | ---------------
|
|
|Income from Continuing Operations (Before Extraordinary Loss and Cumulative Effects of Changes in Accounting Principles) |                                                                                        | $              
|Taxes on Income, Including Tax Effect for BGE Preference Stock Dividends                                                 |                                                                                        |                
|                                                                                                                         |                                                                                        |                
|Adjusted Income                                                                                                          |                                                                                        | $              
|                                                                                                                         |                                                                                        |                
|Fixed Charges:                                                                                                           |                                                                                        |                
|                                                                                                                         | Interest and Amortization of Debt Discount and Expense and Premium on all Indebtedness |                
|                                                                                                                         | Earnings Required for BGE Preference Stock Dividends                                   |                
|                                                                                                                         | Capitalized Interest                                                                   |                
|                                                                                                                         | Interest Factor in Rentals                                                             |                
|                                                                                                                         |                                                                                        |                
|                                                                                                                         | Total Fixed Charges                                                                    |                
|                                                                                                                         |                                                                                        |                
|Amortization of Capitalized Interest                                                                                     |                                                                                        | $              
|                                                                                                                         |                                                                                        |                
|Earnings (1)                                                                                                             |                                                                                        | $              
|                                                                                                                         |                                                                                        |                
|Ratio of Earnings to Fixed Charges                                                                                       |                                                                                        |                

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