**Exhibit        12(b)**

**Tucson        Electric Power Company**Computation        of Ratio of Earnings to Fixed        Charges****

|                                                                                                      |   | 6                  Months                  Ended |   |   | 12                  Months                  Ended |   |    | 12                  Months                  Ended          |   |
|-----------------------------------------------------------------------------------------------------------|--------|--------------------------------------------------|--------|--------|---------------------------------------------------|--------|---------|------------------------------------------------------------|--------|
|                                                                                                      |   | Jun.                  30                         |   |   | Jun.                  30                          |   |    | 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                                                   |   | $                                                | 25,115 |   |                                              | $      | 51,517  |                                                       |   | $ | 51,422 |   |   | $ | 56,243 |   |   | $ | 69,904 |   |   | $ | 76,585 |   |   | $ | 65,620 |   |
|   Other                  Interest (1)                                                           |   |                                             | 2,958  |   |                                              |   | 7,528   |                                                       |   |   | 6,436 |   |   |   | 2,597 |   |   |   | 1,263 |   |   |   | 1,820 |   |   |   | 273 |   |
|   Interest                  on Capital Lease Obligations                                        |   |                                             | 32,266 |   |                                              |   | 67,758  |                                                       |   |   | 72,556 |   |   |   | 79,064 |   |   |   | 85,869 |   |   |   | 84,053 |   |   |   | 87,783 |   |
| **Total                  Fixed Charges**                                                                  |   |                                             | 60,339 |   |                                              |   | 126,803 |                                                       |   |   | 130,414 |   |   |   | 137,904 |   |   |   | 157,036 |   |   |   | 162,458 |   |   |   | 153,676 |   |
|                                                                                                      |   |                                             |   |   |                                              |   |    |                                                       |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| **Net                  Income**                                                                           |   |                                             | 13,092 |   |                                              |   | 52,029  |                                                       |   |   | 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**                                                |   |                                             | 13,092 |   |                                              |   | 52,029  |                                                       |   |   | 66,745 |   |   |   | 48,893 |   |   |   | 46,127 |   |   |   | 61,442 |   |   |   | 55,390 |   |
|                                                                                                      |   |                                             |   |   |                                              |   |    |                                                       |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| **Add                  (Deduct):**                                                                        |   |                                             |   |   |                                              |   |    |                                                       |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|   (Income)                  Losses from Equity Investees (2)                                    |   |                                             | -      |   |                                              |   | (213    | )                                                          |   |   | (320 | ) |   |   | (314 | ) |   |   | (131 | ) |   |   | (76 | ) |   |   | 17 |   |
|   Income                  Taxes                                                                 |   |                                             | 9,435  |   |                                              |   | 32,486  |                                                       |   |   | 42,478 |   |   |   | 33,907 |   |   |   | 34,815 |   |   |   | 21,090 |   |   |   | 36,434 |   |
|   Total                  Fixed Charges                                                          |   |                                             | 60,339 |   |                                              |   | 126,803 |                                                       |   |   | 130,414 |   |   |   | 137,904 |   |   |   | 157,036 |   |   |   | 162,458 |   |   |   | 153,676 |   |
|                                                                                                      |   |                                             |   |   |                                              |   |    |                                                       |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| **Total                    Earnings before Taxesand                    Fixed                    Charges** |   | $                                                | 82,866 |   |                                              | $      | 211,105 |                                                       |   | $ | 239,317 |   |   | $ | 220,390 |   |   | $ | 237,847 |   |   | $ | 244,914 |   |   | $ | 245,517 |   |
|                                                                                                      |   |                                             |   |   |                                              |   |    |                                                       |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
|                                                                                                      |   |                                             |   |   |                                              |   |    |                                                       |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| **Ratio                  of Earnings to Fixed Charges**                                                   |   |                                             | 1.373  |   |                                              |   | 1.665   |                                                       |   |   | 1.835 |   |   |   | 1.598 |   |   |   | 1.515 |   |   |   | 1.508 |   |   |   | 1.598 |   |
|                                                                                                      |   |                                             |   |   |                                              |   |    |                                                       |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |