Exhibit 21.1

Subsidiaries of Duquesne Light Holdings, Inc.



|                                             |  |              
|-------------------------------------------- |  | -------------
|Entity                                       |  | Jurisdiction 
|AquaSource, Inc. (Inactive)                  |  | Delaware     
|                                             | 
|Cherrington Insurance, Ltd.                  |  | Bermuda      
|                                             | 
|DQE Capital Corporation                      |  | Delaware     
|                                             | 
|DQE Enterprises, Inc.                        |  | Pennsylvania 
|Allegheny Development Corporation (Inactive) |  | Pennsylvania 
|BodyMedia, Inc.                              |  | Delaware     
|In-Transition, Inc. (Inactive)               |  | Pennsylvania 
|Lab Cor, Inc.                                |  | Oregon       
|NWP Services Corp.                           |  | Delaware     
|                                             | 
|DQE Financial Corp.                          |  | Delaware     
|Montauk Synfuels, LLC                        |  | Delaware     
|Duquesne Power, LLC                          |  | Delaware     
|Mariner Investment Strategies, LLC.          |  | Delaware     
|Diemen No. 33 LLC                            |  | Delaware     
|Diemen-Flevo Co.                             |  | Delaware     
|Alkmaar, LLC                                 |  | Delaware     
|Schiphol LLC                                 |  | Delaware     
|Holyhead LLC                                 |  | Delaware     
|Maasvlakte LLC                               |  | Delaware     
|Monticello Two Corporation                   |  | Delaware     
|Utrecht LLC                                  |  | Delaware     
|North Shore Affordable Housing, LLC          |  | Delaware     
|                                             | 
|DQE Systems, Inc. (Inactive)                 |  | Pennsylvania 
|DQE Communications, LLC.                     |  | Pennsylvania 
|DQE Communications Network Services LLC      |  | Pennsylvania 
|Duquesne Broadband LLC                       |  | Delaware     
|Duquesne Broadband Smart Grid LLC            |  | Delaware     
|                                             | 
|Duquesne Energy Solutions, LLC               |  | Delaware     
|DES Corporate Services, Inc.                 |  | Delaware     
|DES Operating Services, Inc.                 |  | Delaware     
|DH Energy, L.P. *                            |  | Pennsylvania 
|DQE Synfuels, L.P. *                         |  | Pennsylvania 
|DES Synfuel Operating Services, Inc.         |  | Delaware     
|DH Energy, LLC                               |  | Pennsylvania 
|DH Energy, L.P. *                            |  | Pennsylvania 
|DQE Synfuels LLC                             |  | Delaware     
|DH Canada, Inc.                              |  | New Brunswick
|DQE Synfuels, L.P. *                         |  | Pennsylvania 
|M T Detroit, Inc. (Inactive)                 |  | Delaware     
|DTE Pittsburgh, LLC                          |  | Delaware     
|M T Energy, Inc.                             |  | Pennsylvania 
|                                             | 
|Duquesne Light Company                       |  | Pennsylvania 
|Duquesne Power Two, LLC (Inactive)           |  | Delaware     
|Monongahela Light and Power Company          |  | Pennsylvania 
|DataCom Information Systems, LLC             |  | Delaware     
|Maglev, Inc.                                 |  | Pennsylvania 
|Oakridge Resources, Inc. (Inactive)          |  | Pennsylvania 
|                                             | 
|Duquesne Light Energy, LLC                   |  | Delaware     
|                                             | 
|Duquesne Generation Company                  |  | Pennsylvania 
|Duquesne Conemaugh LLC                       |  | Pennsylvania 
|Duquesne Keystone LLC                        |  | Pennsylvania 

Subsidiaries of Duquesne Light Company



|                                    |  |             
|----------------------------------- |  | ------------
|Entity                              |  | Jurisdiction
|Duquesne Power Two, LLC (Inactive)  |  | Delaware    
|Monongahela Light and Power Company |  | Pennsylvania
|DataCom Information Systems, LLC    |  | Delaware    
|Maglev, Inc.                        |  | Pennsylvania
|Oakridge Resources, Inc. (Inactive) |  | Pennsylvania

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|* | Multiple Parents
|- | ----------------