<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,
                                                          ----------------------------------------------------------------
                                            2000              1999           1998        1997          1996         1995
                                        -----------       ----------   ----------     ----------    --------    ----------
<S>                                     <C>               <C>          <C>            <C>           <C>         <C>
Income before extraordinary item        $   125,772       $  142,179   $  112,410     $  105,709    $116,187    $  117,488

Income taxes                                 82,325           95,321       72,276         72,155      78,340        75,540
                                        -----------       ----------   ----------       --------     -------       -------
Fixed charges:
     Interest on long-term debt
        including amortization of
        discount, premium and
        expense                              77,289           77,790       81,132         78,350      69,329        65,572
     Other interest                           6,215            6,117        9,328         12,835      12,516        10,353
     Preferred dividend require-
        ments of a subsidiary
        trust                                 5,687            5,687        5,688          5,687       1,390             -
                                        -----------       ----------   ----------     ----------   ---------    ----------
        Total fixed charges                  89,191           89,594       96,148         96,872      83,235        75,925
                                        -----------       ----------   ----------     ----------   ---------    ----------

Nonutility capitalized interest                   -                -            -           (208)       (311)         (304)
                                        -----------       ----------   ----------     ----------   ---------    ----------


Earnings before extraordinary
     item, income taxes, and
     fixed charges                      $   297,288       $  327,094   $  280,834     $  274,528    $277,451    $  268,649
                                        ===========       ==========   ==========     ==========   =========   ===========
Fixed charges                           $    89,191       $   89,594   $   96,148     $  $96,872    $ 83,235    $   75,925

Preferred dividend requirements               8,073            7,417        7,150          7,556      14,961        16,185
                                        -----------       ----------   ----------     ----------   ---------   -----------
                                        $    97,264       $   97,011   $  103,298     $  104,428    $ 98,196    $   92,110
                                        ===========       ==========   ==========     ==========   =========   ===========
Ratio of earnings to fixed charges
     and preferred dividends                   3.06             3.37         2.72           2.63        2.83          2.92
</TABLE>

For purposes of computing the ratio, earnings are income before extraordinary
item 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 estimated interest component of rentals. Preferred
dividend requirements represent annualized preferred dividend requirements
multiplied by the ratio that pre-tax income bears to net income.