**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)** |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
|                                                                                                                                                                                                                                                                                   |   |   |   |   |
|                                                                                                                                                                                                                                                                                   | **Nine                  Months** |   | **Year** |   |
|                                                                                                                                                                                                                                                                                   | **Ended** |   | **Ended** |   |
|                                                                                                                                                                                                                                                                                   | **September                  30,** |   | **December                  31,** |   |
|                                                                                                                                                                                                                                                                                   | **2006** |   | **2005** |   |
| Net                  income from continuing operations                                                                                                                                                                                                                                 | $ | 43,380 |   | $ | 42,998 |   |
| Add-                  Taxes based on income                                                                                                                                                                                                                                            |   | 20,538 |   |   | 24,596 |   |
| Net                  income before income taxes                                                                                                                                                                                                                                        |   | 63,918 |   |   | 67,594 |   |
|                                                                                                                                                                                                                                                                                   |   |   |   |   |   |   |
| Add-                  fixed charges:                                                                                                                                                                                                                                                   |   |   |   |   |   |   |
| Interest                  on long term debt                                                                                                                                                                                                                                            |   | 22,345 |   |   | 28,969 |   |
| Estimated                  interest cost within rental expense                                                                                                                                                                                                                         |   | 466 |   |   | - |   |
| Amortization                  of net debt premium, discount,and                  expenses                                                                                                                                                                                              |   | 733 |   |   | 953 |   |
| Total                  fixed charges                                                                                                                                                                                                                                                   |   | 23,544 |   |   | 29,922 |   |
|                                                                                                                                                                                                                                                                                   |   |   |   |   |   |   |
| Earnings                  available for fixed charges                                                                                                                                                                                                                                  |   | 87,462 |   |   | 97,516 |   |
|                                                                                                                                                                                                                                                                                   |   |   |   |   |   |   |
| Ratio                  of earnings to fixed charges                                                                                                                                                                                                                                    |   | 3.71 |   |   | 3.25 |   |
|                                                                                                                                                                                                                                                                                   |   |   |   |   |   |   |
| Earnings                  required for combined fixedcharges                  and preferred stock dividends:                                                                                                                                                                           |   |   |   |   |   |   |
| Preferred                  stock dividends                                                                                                                                                                                                                                             |   | 1,884 |   |   | 2,512 |   |
| Adjustment                  to pre-tax basis                                                                                                                                                                                                                                           |   | 892 |   |   | 1,437 |   |
|                                                                                                                                                                                                                                                                                   |   | 2,776 |   |   | 3,949 |   |
|                                                                                                                                                                                                                                                                                   |   |   |   |   |   |   |
| Combined                  fixed charges and preferred stockdividend                  requirements                                                                                                                                                                                      | $ | 26,320 |   | $ | 33,871 |   |
|                                                                                                                                                                                                                                                                                   |   |   |   |   |   |   |
| Ratio                  of earnings to combined fixed chargesand                  preferred stock dividend requirements                                                                                                                                                                 |   | 3.32 |   |   | 2.87 |   |
|                                                                                                                                                                                                                                                                                   |   |   |   |   |   |   |