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Exhibit 12.1

Computation of Ratio of Earnings to Fixed Charges
Atlantic Power Corporation

The following table sets forth the ratio of earnings to fixed charges for the periods indicated below.

|  |  |  | Year Ended December 31, |
--- | --- | --- | --- | --- | ---
|  | Six Months Ended June 30, 2013 |
(in millions of U.S. dollars) |  | 2012 |  | 2011 |  | 2010 |  | 2009 |  | 2008 |
Earnings (loss) from continuing operations before income taxes |  | $ | 6.9 |  | $ | (143.7 | ) | $ | (82.9 | ) | $ | (12.0 | ) | $ | (82.7 | ) | $ | (2.6 | )
Loss attributable to noncontrolling interests |  |  | (0.8 | ) |  | 0.6 |  |  | 0.5 |  |  | 0.1 |  |  | — |  |  | — |
Distributions from equity investments |  |  | 18.1 |  |  | 38.3 |  |  | 21.9 |  |  | 16.8 |  |  | 27.8 |  |  | 41.0 |
Interest capitalized |  |  | (1.6 | ) |  | (16.9 | ) |  | (2.9 | ) |  | (5.0 | ) |  | — |  |  | — |
Preferred share dividends of a subsidiary company |  |  | (6.3 | ) |  | (13.0 | ) |  | (3.2 | ) |  | — |  |  | — |  |  | — |
Fixed charges (from below) |  |  | 79.4 |  |  | 151.4 |  |  | 52.1 |  |  | 34.3 |  |  | 74.7 |  |  | 61.0 |
|  | $ | 95.7 |  | $ | 16.7 |  | $ | (14.5 | ) | $ | 34.2 |  | $ | 19.8 |  | $ | 99.4 |
Preferred share dividends of a subsidiary company |  | $ | 6.3 |  | $ | 13.0 |  | $ | 3.2 |  | $ | — |  | $ | — |  | $ | — |
Project level interest |  | $ | 21.9 |  | $ | 44.9 |  | $ | 22.9 |  | $ | 22.6 |  | $ | 18.7 |  | $ | 17.7 |
Corporate level interest |  |  | 51.2 |  |  | 93.5 |  |  | 26.0 |  |  | 11.7 |  |  | 56.0 |  |  | 43.3 |
|  | $ | 79.4 |  | $ | 151.4 |  | $ | 52.1 |  | $ | 34.3 |  | $ | 74.7 |  | $ | 61.0 |
Ratio of earnings to fixed charges |  |  | 1.21 |  |  | (1) |  |  | (1) |  |  | 1.00 |  |  | (1) |  |  | 1.63 |

(1)
  Our ratio of earnings to fixed charges is computed by dividing earnings by fixed charges. For these purposes, "earnings" is the amount resulting from adding together earnings (loss) from continuing operations before income taxes, distributions from equity investments and fixed charges and subtracting loss attributable to noncontrolling interests, interest capitalized and preferred share dividends of a subsidiary company. "Fixed charges" is the amount resulting from adding together preferred share dividends of a subsidiary company, project level interest (including interest capitalized and interest from discontinued operations) and corporate level interest expenses. Earnings were insufficient to cover fixed charges by $134.7 million, $66.6 million and $54.9 million for the years ended December 31, 2012, 2011 and 2009, respectively, due to a loss from continuing operations before taxes of $143.7, $82.9 and $82.7, for the years ended December 31, 2012, 2011 and 2009, respectively.

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Exhibit 12.1

Computation of Ratio of Earnings to Fixed Charges Atlantic Power Corporation