Exhibit 12.1 Boston Edison Company Computation of Ratio of Earnings to Fixed Charges Year ended December 31, 1997 (in thousands) Net income from continuing operations $144,642 Income taxes 82,455 Fixed charges 116,258 -------- Total $343,355 ======== Interest expense $106,899 Interest component of rentals 9,359 -------- Total $116,258 ======== Ratio of earnings to fixed charges 2.95 ====