<PAGE>

                                                                    Exhibit 12-B


                         Delmarva Power & Light Company

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



<TABLE>
<CAPTION>

                                                                Year Ended December 31,
                                            --------------------------------------------------------------
<S>                                         <C>          <C>          <C>          <C>          <C>
                                               1999         1998         1997         1996         1995
                                            ----------   ----------   ----------   ----------   ----------

Income before extraordinary item             $142,179     $112,410     $105,709     $116,187     $117,488
                                            ----------   ----------   ----------   ----------   ----------
Income taxes                                   95,321       72,276       72,155       78,340       75,540
                                            ----------   ----------   ----------   ----------   ----------

Fixed charges:
        Interest on long-term debt
            including amortization of
            discount, premium and
            expense                            77,790       81,132       78,350       69,329       65,572
        Other interest                          6,117        9,328       12,835       12,516       10,353
        Preferred dividend require-
            ments of a subsidiary
            trust                               5,687        5,688        5,687        1,390            -
                                            ----------   ----------   ----------   ----------   ----------
            Total fixed charges                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                        $327,094     $280,834     $274,528     $277,451     $268,649
                                            ----------   ----------   ----------   ----------   ----------

Fixed charges                                 $89,594      $96,148      $96,872      $83,235      $75,925

Preferred dividend requirements                 7,417        7,150        7,556       14,961       16,185
                                            ----------   ----------   ----------   ----------   ----------
                                              $97,011     $103,298     $104,428      $98,196      $92,110
                                            ----------   ----------   ----------   ----------   ----------

Ratio of earnings to fixed charges
        and preferred dividends                  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.