EXHIBIT 12.1 ALLEGHENY ENERGY SUPPLY COMPANY, LLC COMPUTATION IN SUPPORT OF RATIO OF EARNINGS TO FIXED CHARGES (UNAUDITED) ------------------------------------------------------------------------ From November Nine Months Twelve Months Twelve Months 18 Inception Ended Ended Ended Date through September 30, September 30, December 31, December 31, 2001 2001 2000 1999 ---------------- ----------------- ----------------- ----------------- Earnings: (Thousands of Dollars) Net income* $ 234,857 $ 268,857 $ 77,996 $ 9,532 Plus: Fixed charges (see below) 82,895 96,963 39,505 2,378 Income taxes* 129,044 146,404 36,081 2,503 Amortization of capitalized interest 144 182 110 7 Income distributions of equity investees -- -- 7,200 -- Less: Capitalized interest (4,546) (5,022) (4,337) (212) Income from unconsolidated equity investees -- -- (5,665) -- --------- --------- --------- --------- Total Earnings $ 442,394 $ 507,384 $ 150,890 $ 14,208 --------- --------- --------- --------- Fixed Charges: Interest on long-term debt $ 42,073 $ 51,466 $ 29,221 $ 2,135 Other interest 36,520 40,653 8,574 170 Estimated interest component of rentals 4,302 4,844 1,710 73 --------- --------- --------- --------- Total Fixed Charges $ 82,895 $ 96,963 $ 39,505 $ 2,378 --------- --------- --------- --------- Ratio of Earnings to Fixed Charges 5.34 5.23 3.82 5.97 ========= ========= ========= ========= * Net income and income taxes exclude extraordinary charges, minority interest and accounting changes.