EXHIBIT NO. 12(a)

CONSTELLATION ENERGY GROUP, INC. AND SUBSIDIARIESCOMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES

|                                                                                                                        |                                                                                        | 12 Months Ended
|----------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------- | ---------------
|
|
|Income from Continuing Operations (Before Extraordinary Loss and Cumulative Effect 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                                                                                      |                                                                                        |                

134

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