Exhibit 12 TUCSON ELECTRIC POWER COMPANY COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES 9 Months 12 Months Ended Ended ---------------------------------------------------------------- Sep. 30, Sep. 30, Dec. 31, Dec. 31, Dec. 31, Dec. 31, Dec. 31, 2002 2002 2001 2000 1999 1998 1997 - ----------------------------------------------------------------------------------------------------------------------- - Thousands of dollars - Fixed Charges: Interest on Long-Term Debt $ 42,649 $ 57,196 $ 61,218 $ 66,377 $ 66,836 $ 72,672 $ 66,247 Other Interest(1) 5,882 7,961 8,058 9,067 13,081 13,207 9,640 Interest on Capital Lease Obligations(2) 65,726 87,807 90,348 92,658 82,414 81,823 83,019 - ----------------------------------------------------------------------------------------------------------------------- Total Fixed Charges 114,257 152,964 159,624 168,102 162,331 167,702 158,906 Net Income 42,099 60,528 75,284 51,169 73,475 41,676 83,572 Less: Extraordinary Income & Accounting Change - Net of Tax - - 470 - 22,597 - - - ----------------------------------------------------------------------------------------------------------------------- Net Income from Continuing Operations 42,099 60,528 74,814 51,169 50,878 41,676 83,572 Add (Deduct): Losses from Equity Investees 279 431 700 1,543 - - - Income Taxes 27,367 39,557 55,910 26,566 22,350 17,578 (22,104) Total Fixed Charges 114,257 152,964 159,624 168,102 162,331 167,702 158,906 - ----------------------------------------------------------------------------------------------------------------------- Total Earnings before Taxes and Fixed Charges $184,002 $253,480 $291,048 $247,380 $235,559 $226,956 $220,374 ======================================================================================================================= Ratio of Earnings to Fixed Charges 1.610 1.657 1.823 1.472 1.451 1.353 1.387 <FN> (1) Excludes recognition of Allowance for Borrowed Funds Used During Construction. (2) Amount has been restated for years ended 2001 - 2000 to conform to current year's presentation. </FN>