Exhibit 12.3
WISCONSIN POWER AND LIGHT COMPANY
RATIO OF EARNINGS TO FIXED CHARGES AND RATIO OF EARNINGS TO COMBINED FIXED CHARGES
AND PREFERRED DIVIDEND REQUIREMENTS

| Nine Months Ended |  |  |  |  |  |
| September 30, |  | Years Ended December 31,
| 2012 |  | 2011 |  | 2011 | 2010 | 2009 | 2008 | 2007
| (dollars in millions)
EARNINGS: |  |  |  |  |  |  |  |  |
Net income |  | $124.7 |  |  |  | $120.8 |  |  |  | $163.5 |  |  | $152.3 |  |  | $89.5 |  |  | $118.4 |  |  | $113.5 |
Income taxes (a) | 75.5 |  |  | 59.6 |  |  | 81.9 |  | 98.3 |  | 45.8 |  | 68.4 |  | 59.3 |
Income before income taxes | 200.2 |  |  | 180.4 |  |  | 245.4 |  | 250.6 |  | 135.3 |  | 186.8 |  | 172.8 |
Fixed charges as defined | 80.6 |  |  | 80.7 |  |  | 103.3 |  | 101.6 |  | 99.9 |  | 90.7 |  | 84.8 |
Adjustment for undistributed equity earnings | (5.5 | ) |  | (4.5 | ) |  | (6.4 | ) | (5.6 | ) | (7.1 | ) | (6.1 | ) | (6.7 | )
Total earnings as defined |  | $275.3 |  |  |  | $256.6 |  |  |  | $342.3 |  |  | $346.6 |  |  | $228.1 |  |  | $271.4 |  |  | $250.9 |
FIXED CHARGES: |  |  |  |  |  |  |  |  |
Interest expense |  | $59.6 |  |  |  | $60.0 |  |  |  | $79.9 |  |  | $78.6 |  |  | $74.8 |  |  | $62.2 |  |  | $49.6 |
Estimated interest component of rent expense | 21.0 |  |  | 20.7 |  |  | 23.4 |  | 23.0 |  | 25.1 |  | 28.5 |  | 35.2 |
Total fixed charges as defined |  | $80.6 |  |  |  | $80.7 |  |  |  | $103.3 |  |  | $101.6 |  |  | $99.9 |  |  | $90.7 |  |  | $84.8 |
Ratio of Earnings to Fixed Charges | 3.42 |  |  | 3.18 |  |  | 3.31 |  | 3.41 |  | 2.28 |  | 2.99 |  | 2.96 |
Preferred dividend requirements (pre-tax basis) (b) |  | $4.0 |  |  |  | $3.7 |  |  |  | $5.0 |  |  | $5.4 |  |  | $5.0 |  |  | $5.2 |  |  | $5.0 |
Fixed charges and preferred dividend requirements |  | $84.6 |  |  |  | $84.4 |  |  |  | $108.3 |  |  | $107.0 |  |  | $104.9 |  |  | $95.9 |  |  | $89.8 |
Ratio of Earnings to Combined Fixed Charges and Preferred Dividend Requirements | 3.25 |  |  | 3.04 |  |  | 3.16 |  | 3.24 |  | 2.17 |  | 2.83 |  | 2.79 |

(a) Includes net interest related to unrecognized tax benefits.
(b) Preferred dividend requirements (pre-tax basis) are computed by dividing the preferred dividend requirements by one hundred percent minus the respective year-to-date effective income tax rate.