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                                                                    EXHIBIT 12.1

                                   PUBLIC SERVICE ELECTRIC AND GAS COMPANY
                              COMPUTATION OF RATIOS OF EARNINGS TO FIXED CHARGES

<TABLE>
<CAPTION>
                                                      FOR THE NINE
                                                      MONTHS ENDED                          FOR THE YEARS ENDED
                                                      SEPTEMBER 30,                             DECEMBER 31,
                                                  --------------------------------------------------------------------------------
                                                    2005        2004        2004        2003        2002        2001        2000
                                                  --------------------------------------------------------------------------------
                                                                             (MILLIONS, EXCEPT RATIOS)
<S>                                               <C>         <C>         <C>         <C>         <C>         <C>         <C>
Earnings as Defined in Regulation S-K (A):

Pre-tax Income from Continuing Operations         $    473    $    476    $    592    $    376    $    320    $    324    $    994
Fixed Charges                                          256         273         362         390         408         461         447
                                                  --------------------------------------------------------------------------------
Total Earnings                                    $    729    $    749    $    954    $    766    $    728    $    785    $  1,441
                                                  ================================================================================

Fixed Charges as Defined in Regulation S-K (B)

Interest Expense                                  $    256    $    273    $    362    $    390    $    406    $    458    $    444
Interest Factor in Rentals                              --          --          --          --           2           3           3
                                                  --------------------------------------------------------------------------------
Total Fixed Charges                               $    256    $    273    $    362    $    390    $    408    $    461    $    447
                                                  ================================================================================

Ratio of Earnings to Fixed Charges                    2.85        2.74        2.64        1.96        1.78        1.70        3.22
                                                  ================================================================================
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(A)   The term "earnings" shall be defined as pretax income from continuing
      operations. Add to pretax income the amount of fixed charges adjusted to
      exclude the amount of any interest capitalized during the period.

(B)   Fixed Charges represent (a) interest, whether expensed or capitalized, (b)
      amortization of debt discount, premium and expense and (c) an estimate of
      interest implicit in rentals.