| Ameren      Energy Generating CompanyComputation      of Ratio of Earnings to Fixed Charges(Thousands      of Dollars, Except Ratios) |                |
|---------------------------------------------------------------------------------------------------------------------------------------|---------------------|
|                                                                                                                                  |                |   |   |   |   |
|                                                                                                                                  |                |   |   |   |   |
|                                                                                                                                  | 9      Months Ended |   |   | Year      Ended |   |
|                                                                                                                                  | September      30,  |   |   | December      31, |   |
|                                                                                                                                  | 2008                |   |   | 2007 |   |
| Net      income from continuing operations                                                                                            | $                   | 140,181 |   |   | $ | 124,894 |   |
| Add-      Taxes based on income                                                                                                       |                | 81,602 |   |   |   | 77,799 |   |
|                                                                                                                                  |                |   |   |   |   |   |   |
| Net      income before income taxes                                                                                                   |                | 221,783 |   |   |   | 202,693 |   |
|                                                                                                                                  |                |   |   |   |   |   |   |
| Add-      fixed charges:                                                                                                              |                |   |   |   |   |   |   |
| Interest on long term      debt  (1)                                                                                        |                | 39,631 |   |   |   | 54,783 |   |
| Estimated      interest cost within rental expense                                                                                    |                | 137 |   |   |   | 164 |   |
| Amortization      of net debt premium, discount,     and      expenses                                       |                | 550 |   |   |   | 586 |   |
|                                                                                                                                  |                |   |   |   |   |   |   |
| Total      fixed charges                                                                                                              |                | 40,318 |   |   |   | 55,533 |   |
|                                                                                                                                  |                |   |   |   |   |   |   |
| Earnings      available for fixed charges                                                                                             | $                   | 262,101 |   |   | $ | 258,226 |   |
|                                                                                                                                  |                |   |   |   |   |   |   |
| Ratio      of earnings to fixed charges                                                                                               |                | 6.50 |   |   |   | 4.64 |   |