<PAGE>

                                                     DUQUESNE LIGHT EXHIBIT 12.1

                     Duquesne Light Company and Subsidiary

               Calculation of Ratio of Earnings to Fixed Charges
                            (Thousands of Dollars)
<TABLE>
<CAPTION>
                                                                                  Year Ended December 31,
                                                                   ----------------------------------------------------
                                                                     1999       1998       1997       1996       1995
                                                                   --------   --------   --------   --------   --------
<S>                                                                <C>        <C>        <C>        <C>        <C>
FIXED CHARGES:
  Interest on long-term debt                                       $ 76,938   $ 75,810   $ 81,592   $ 82,505   $ 89,139
  Other interest                                                      4,809      1,290        752      1,632      2,599
  Monthly Income Preferred Securities dividend requirements          12,562     12,562     12,562      7,921         --
  Amortization of debt discount, premium and expense-net              2,516      5,266      5,828      5,973      6,252
  Portion of lease payments representing an interest factor          42,973     44,146     44,208     44,357     44,386
                                                                   --------   --------   --------   --------   --------
    Total Fixed Charges                                            $139,798   $139,074   $144,942   $142,388   $142,376
                                                                   --------   --------   --------   --------   --------


EARNINGS:
  Income from continuing operations                                $151,020   $148,548   $141,820   $149,860   $151,070
  Income taxes                                                       76,127*    74,912*    73,838*    83,008*    92,894*
  Fixed charges as above                                            139,798    139,074    144,942    142,388    142,376
                                                                   --------   --------   --------   --------   --------

    Total Earnings                                                 $366,945   $362,534   $360,600   $375,256   $386,340
                                                                   --------   --------   --------   --------   --------

RATIO OF EARNINGS TO FIXED CHARGES                                     2.62       2.61       2.49       2.64       2.71
                                                                  =========   ========   ========   ========   ========
</TABLE>

  *Earnings related to income taxes reflect a $3.0, $12.0 million, $17.0
million, $12.0 million and $13.5 million decrease for the twelve months ended
December 31, 1999, 1998, 1997, 1996 and 1995, respectively, due to a financial
statement reclassification related to Statement of Financial Accounting
Standards No. 109, Accounting for Income Taxes. The ratio of earnings to fixed
charges, absent this reclassification equals 2.65, 2.69, 2.61, 2.72 and 2.81 for
the twelve months ended December 31, 1999, 1998, 1997, 1996 and 1995,
respectively.