**Exhibit      12.3**| **Central                Illinois Public Service Company****Computation                of Ratios of Earnings to Fixed Charges and Combined****Fixed                Charges and Preferred Stock Dividend Requirements****(Thousands                of Dollars, Except Ratios)** |                              |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------|
|                                                                                                                                                                                                                                                                           |                              |   |   |   |   |
|                                                                                                                                                                                                                                                                           |                              |   |   |   |   |
|                                                                                                                                                                                                                                                                           | **6                Months Ended** |   |   | **Year                Ended** |   |
|                                                                                                                                                                                                                                                                           | **June                30,**       |   |   | **December                31,** |   |
|                                                                                                                                                                                                                                                                           | **2007**                          |   |   | **2006** |   |
| Net                income from continuing operations                                                                                                                                                                                                                           | $                                 | 16,640 |   |   | $ | 37,372 |   |
| Add-                Taxes based on income                                                                                                                                                                                                                                      |                              | 8,605 |   |   |   | 15,539 |   |
| Net                income before income taxes                                                                                                                                                                                                                                  |                              | 25,245 |   |   |   | 52,911 |   |
|                                                                                                                                                                                                                                                                           |                              |   |   |   |   |   |   |
| Add-                fixed charges:                                                                                                                                                                                                                                             |                              |   |   |   |   |   |   |
| Interest                on long term debt                                                                                                                                                                                                                                      |                              | 17,817 |   |   |   | 29,932 |   |
| Estimated                interest cost within rental expense                                                                                                                                                                                                                   |                              | 423 |   |   |   | 726 |   |
| Amortization                of net debt premium, discount,     and                expenses                                                                                                                                                            |                              | 593 |   |   |   | 1,025 |   |
| Total                fixed charges                                                                                                                                                                                                                                             |                              | 18,833 |   |   |   | 31,683 |   |
|                                                                                                                                                                                                                                                                           |                              |   |   |   |   |   |   |
| Earnings                available for fixed charges                                                                                                                                                                                                                            |                              | 44,078 |   |   |   | 84,594 |   |
|                                                                                                                                                                                                                                                                           |                              |   |   |   |   |   |   |
| Ratio                of earnings to fixed charges                                                                                                                                                                                                                              |                              | 2.34 |   |   |   | 2.67 |   |
|                                                                                                                                                                                                                                                                           |                              |   |   |   |   |   |   |
| Earnings                required for combined fixedcharges                and preferred stock dividends:                                                                                                                                                                       |                              |   |   |   |   |
| Preferred                stock dividends                                                                                                                                                                                                                                       |                              | 1,256 |   |   |   | 2,512 |   |
| Adjustment                to pre-tax basis                                                                                                                                                                                                                                     |                              | 650 |   |   |   | 1,045 |   |
|                                                                                                                                                                                                                                                                           |                              | 1,906 |   |   |   | 3,557 |   |
|                                                                                                                                                                                                                                                                           |                              |   |   |   |   |   |   |
| Combined                fixed charges and preferred stockdividend                requirements                                                                                                                                                                                  | $                                 | 20,739 |   |   | $ | 35,240 |   |
|                                                                                                                                                                                                                                                                           |                              |   |   |   |   |   |   |
| Ratio                of earnings to combined fixed chargesand                preferred stock dividend requirements                                                                                                                                                             |                              | 2.12 |   |   |   | 2.40 |   |
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