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 Change in Accounting Principle) |                                                                                        | $              
|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                                                                    |                
|                                                                                                                      |                                                                                        |                
|Earnings(1)                                                                                                           |                                                                                        | $              
|                                                                                                                      |                                                                                        |                
|Ratio of Earnings to Fixed Charges                                                                                    |                                                                                        |                

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