<PAGE>

                                                                    Exhibit 12-B

                        Delmarva Power & Light Company

          Ratio of Earnings to Fixed Charges and Preferred Dividends
                            (Dollars in Thousands)

<TABLE> 
<CAPTION> 
                                              12 Months 
                                                 Ended  
                                            September 30,                         Year  Ended  December  31,
                                                              ------------------------------------------------------------------
                                                 1998           1997           1996           1995          1994         1993 
                                            -------------     --------       --------       --------      -------      -------
<S>                                         <C>               <C>            <C>           <C>            <C>          <C> 
Net income                                     $117,464        $105,709      $116,187      $117,488       $108,310     $111,076 
                                               --------        --------      --------      --------       --------     --------  
                                                                                                                                
Income taxes                                     76,422          72,155        78,340        75,540         67,613       67,102 
                                               --------        --------      --------      --------       --------     --------  
                                                                                                                                
Fixed charges:                                                                                                                  
   Interest on long-term debt                                                                                                   
        including amortization of                                                                                               
        discount, premium and                                                                                                   
        expense                                  80,916          78,350        69,329        65,572         61,128       62,651 
   Other interest                                10,155          12,835        12,516        10,353          9,336        9,245 
   Preferred dividend require-                                                                                                  
        ments of a subsidiary                                                                                                   
        trust                                     5,687           5,687         1,390             -              -            - 
                                               --------        --------      --------      --------       --------     -------- 
        Total fixed charges                      96,758          96,872        83,235        75,925         70,464       71,896 
                                               --------        --------      --------      --------       --------     --------  
                                                                          
Nonutility capitalized interest                       -            (208)         (311)         (304)          (256)        (246)
                                               --------        --------      --------      --------       --------     --------  
                                                                                                                                 
Earnings before income taxes                                                                                                     
   and fixed charges                           $290,644        $274,528      $277,451      $268,649       $246,131     $249,828 
                                               --------        --------      --------      --------       --------     --------  
                                                                                                                                 
Fixed charges                                  $ 96,758        $ 96,872      $ 83,235      $ 75,925       $ 70,464     $ 71,896 
                                                                                                                                 
Preferred dividend requirements                   7,195           7,556        14,961        16,185         15,948       14,803 
                                               --------        --------      --------      --------       --------     --------  
                                                                                                                                 
                                               $103,953        $104,428      $ 98,196      $ 92,110       $ 86,412     $ 86,699
                                               --------        --------      --------      --------       --------     -------- 
                                                                                 
Ratio of earnings to fixed charges                                                                                     
   and preferred dividends                         2.80            2.63          2.83          2.92           2.85         2.88
</TABLE> 

For purposes of computing the ratio, earnings are net income plus income taxes
and fixed charges, less nonutility capitalized interest. Fixed charges consist
of interest on long- and short-term debt, amortization of debt discount,
premium, and expense, dividends on preferred securities of a subsidiary trust,
plus the interest factor associated with the Company's major leases, and one-
third of the remaining annual rentals. Preferred dividend requirements represent
annualized preferred dividend requirements multiplied by the ratio that pre-tax
income bears to net income.

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