**Exhibit      12B**

**Tucson      Electric Power CompanyComputation of Ratio of Earnings to Fixed      Charges**

|                                                                    | 3                  MonthsEnded |   | 12                  MonthsEnded |   | 12                  Months                  Ended          |   |
|-------------------------------------------------------------------------|--------------------------------|--------|---------------------------------|--------|------------------------------------------------------------|--------|
|                                                                    | Mar.                  31       |   | Mar.                  31        |   | Dec.                  31,                                  |   | Dec.                  31, |   | Dec.                  31, |   | Dec.                  31, |   | Dec.                  31, |   |
|                                                                    | 2007                           |   | 2007                            |   | 2006                                                       |   | 2005 |   | 2004 |   | 2003 |   | 2002 |   |
|                                                                    |                           |   |                            |   | -                  Thousands                  of Dollars - |   |
| **Fixed                  Charges:**                                     |                           |   |                            |   |                                                       |   |   |   |   |   |   |   |   |   |
| Interest                  on                  Long-Term Debt            | $                              | 12,439 |                            | $      | 51,213                                                     |   | $ | 51,422 |   | $ | 56,243 |   | $ | 69,904 |   | $ | 76,585 |   | $ | 65,620 |   |
| Other                  Interest (1)                                     |                           | 1,559  |                            |   | 7,026                                                      |   |   | 6,436 |   |   | 2,597 |   |   | 1,263 |   |   | 1,820 |   |   | 273 |   |
| Interest                  on                  Capital Lease Obligations |                           | 16,146 |                            |   | 70,163                                                     |   |   | 72,556 |   |   | 79,064 |   |   | 85,869 |   |   | 84,053 |   |   | 87,783 |   |
| **Total                  Fixed Charges**                                |                           | 30,144 |                            |   | 128,402                                                    |   |   | 130,414 |   |   | 137,904 |   |   | 157,036 |   |   | 162,458 |   |   | 153,676 |   |
|                                                                    |                           |   |                            |   |                                                       |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| **Net                  Income**                                         |                           | 821    |                            |   | 50,979                                                     |   |   | 66,745 |   |   | 48,267 |   |   | 46,127 |   |   | 128,913 |   |   | 55,390 |   |
|                                                                    |                           |   |                            |   |                                                       |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| **Less:**                                                               |                           |   |                            |   |                                                       |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Cumulative                    Effect of Accounting Change -Net of Tax   |                           | -      |                            |   | -                                                          |   |   | - |   |   | (626 | ) |   | - |   |   | 67,471 |   |   | - |   |
| **Net                  Income from Continuing Operations**              |                           | 821    |                            |   | 50,979                                                     |   |   | 66,745 |   |   | 48,893 |   |   | 46,127 |   |   | 61,442 |   |   | 55,390 |   |
|                                                                    |                           |   |                            |   |                                                       |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| **Add                  (Deduct):**                                      |                           |   |                            |   |                                                       |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| (Income)                  Losses from Equity Investees (2)              |                           | -      |                            |   | (267                                                       | )      |   | (320 | ) |   | (314 | ) |   | (131 | ) |   | (76 | ) |   | 17 |   |
| Income                  Taxes                                           |                           | 1,068  |                            |   | 32,017                                                     |   |   | 42,478 |   |   | 33,907 |   |   | 34,815 |   |   | 21,090 |   |   | 36,434 |   |
| Total                  Fixed                  Charges                   |                           | 30,144 |                            |   | 128,402                                                    |   |   | 130,414 |   |   | 137,904 |   |   | 157,036 |   |   | 162,458 |   |   | 153,676 |   |
|                                                                    |                           |   |                            |   |                                                       |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| **Total                  Earnings before Taxesand Fixed Charges**       | $                              | 32,033 |                            | $      | 211,131                                                    |   | $ | 239,317 |   | $ | 220,390 |   | $ | 237,847 |   | $ | 244,914 |   | $ | 245,517 |   |
|                                                                    |                           |   |                            |   |                                                       |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| **Ratio                  of Earnings to Fixed Charges**                 |                           | 1.063  |                            |   | 1.644                                                      |   |   | 1.835 |   |   | 1.598 |   |   | 1.515 |   |   | 1.508 |   |   | 1.598 |   |