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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | - | ------------------ | - | -------------------------------- | - | ------ | - | ------ | - | ------ | - | ----------
|Western Massachusetts Electric Company                                                                                                                                         |   |                    |   |                                  |   |        |   |        |   |        |   | Exhibit 12
|Ratio of Earnings to Fixed Charges                                                                                                                                             |   |                    |   |                                  |   |        |   |        |   |        |   |           
|                                                                                                                                                                               |   |                    |   |                                  |   |        |   |        |   |        |   |           
|                                                                                                                                                                               |   | Nine Months        |   |                                  |   |        |   |        |   |        |   |           
|(Thousands of Dollars)                                                                                                                                                         |   | Ended              |   |                                  |   |        |   |        |   |        |   |           
|                                                                                                                                                                               |   | September 30, 2009 |   | For the Years Ended December 31,
|                                                                                                                                                                               |   | (unaudited)        |   | 2008                             |   | 2007   |   | 2006   |   | 2005   |   | 2004      
|Earnings, as defined:                                                                                                                                                          |   |                    |   |                                  |   |        |   |        |   |        |   |           
|Net income                                                                                                                                                                     | $ | 20,462             | $ | 18,330                           | $ | 23,604 | $ | 15,644 | $ | 15,085 | $ | 12,373    
|Income tax expense                                                                                                                                                             |   | 11,764             |   | 10,545                           |   | 14,586 |   | 7,766  |   | 9,294  |   | 7,187     
|Equity in (earnings)/losses of regional nuclear                                                                                                                                |   |                    |   |                                  |   |        |   |        |   |        |   |           
|generating companies                                                                                                                                                           |   | (64)               |   | (101)                            |   | (526)  |   | 241    |   | (311)  |   | (149)     
|Dividends received from regional equity investees                                                                                                                              |   | 419                |   | -                                |   | 701    |   | 372    |   | 103    |   | 687       
|Fixed charges, as below                                                                                                                                                        |   | 15,622             |   | 21,910                           |   | 22,162 |   | 21,087 |   | 19,801 |   | 17,156    
|Less: Interest capitalized (including AFUDC)                                                                                                                                   |   | (172)              |   | (1,010)                          |   | (983)  |   | (853)  |   | (455)  |   | (220)     
|Total earnings, as defined                                                                                                                                                     | $ | 48,031             | $ | 49,674                           | $ | 59,544 | $ | 44,257 | $ | 43,517 | $ | 37,034    
|                                                                                                                                                                               |   |                    |   |                                  |   |        |   |        |   |        |   |           
|Fixed charges, as defined:                                                                                                                                                     |   |                    |   |                                  |   |        |   |        |   |        |   |           
|Interest on long-term debt (a)                                                                                                                                                 | $ | 10,531             | $ | 13,244                           | $ | 11,577 | $ | 10,671 | $ | 9,535  | $ | 6,655     
|Interest on rate reduction bonds                                                                                                                                               |   | 3,337              |   | 5,133                            |   | 5,839  |   | 6,723  |   | 7,570  |   | 8,332     
|Other interest (b)                                                                                                                                                             |   | 632                |   | 1,256                            |   | 2,430  |   | 1,507  |   | 1,041  |   | 782       
|Rental interest factor                                                                                                                                                         |   | 950                |   | 1,267                            |   | 1,333  |   | 1,333  |   | 1,200  |   | 1,167     
|Interest capitalized (including AFUDC)                                                                                                                                         |   | 172                |   | 1,010                            |   | 983    |   | 853    |   | 455    |   | 220       
|Total fixed charges, as defined                                                                                                                                                | $ | 15,622             | $ | 21,910                           | $ | 22,162 | $ | 21,087 | $ | 19,801 | $ | 17,156    
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|                                                                                                                                                                               |   |                    |   |                                  |   |        |   |        |   |        |   |           
|Ratio of Earnings to Fixed Charges                                                                                                                                             |   | 3.07               |   | 2.27                             |   | 2.69   |   | 2.10   |   | 2.20   |   | 2.16      
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|(a)
Interest on long-term debt amounts include amortized premiums, discounts and capitalized expenses related to indebtedness.                                                 |   |                    |  
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|(b)
For the nine months ended September 30, 2009 and for the year ended December 31, 2008, other interest includes interest related to accounting for uncertain tax positions.