Exhibit 21-1



EXELON CORPORATION SUBSIDIARY LISTING



|                                                |  |                          |  | 
|----------------------------------------------- |  | ------------------------ |  | 
|Affiliates                                      |  | Jurisdiction ofFormation |  | 
|Adwin Equipment Company                         |  | Pennsylvania             |  | 
|Adwin Realty Company                            |  | Pennsylvania             |  | 
|AllEnergy Gas & Electric Marketing Company, LLC |  | Delaware                 |  | 
|Ambassador II Joint Venture                     |  | Pennsylvania             |  | 
|AmerGen Clinton NQF, LLC                        |  | Nevada                   |  | 
|AmerGen Consolidation, LLC                      |  | Nevada                   |  | 
|AmerGen Energy Company, LLC                     |  | Delaware                 |  | 
|AmerGen Oyster Creek NQF, LLC                   |  | Nevada                   |  | 
|AmerGen TMI NQF, LLC                            |  | Nevada                   |  | 
|ATNP Finance Company                            |  | Delaware                 |  | 
|Braidwood 1 NQF, LLC                            |  | Nevada                   |  | 
|Braidwood 2 NQF, LLC                            |  | Nevada                   |  | 
|Byron I NQF, LLC                                |  | Nevada                   |  | 
|Byron 2 NQF, LLC                                |  | Nevada                   |  | 
|Cenesco Company, LLC                            |  | Delaware                 |  | 
|ComEd Financing II                              |  | Delaware                 |  | 
|ComEd Financing III                             |  | Delaware                 |  | 
|ComEd Funding, LLC                              |  | Delaware                 |  | 
|ComEd Transitional Funding Trust                |  | Delaware                 |  | 
|Commonwealth Edison Company                     |  | Illinois                 |  | 
|Commonwealth Edison Company of Indiana, Inc.    |  | Indiana                  |  | 
|Concomber, Ltd.                                 |  | Bermuda                  |  | 
|Dresden 1 NQF, LLC                              |  | Nevada                   |  | 
|Dresden 2 NQF, LLC                              |  | Nevada                   |  | 
|Dresden 3 NQF, LLC                              |  | Nevada                   |  | 
|ECP Telecommunications Holdings, LLC            |  | Delaware                 |  | 
|ECPH, LLC                                       |  | Delaware                 |  | 
|Edison Development Canada Inc.                  |  | Ontario                  |  | 
|Edison Finance Partnership                      |  | Canada                   |  | 
|EEI Telecommunications Holdings, LLC            |  | Delaware                 |  | 
|EGW Meter Services, LLC                         |  | Delaware                 |  | 
|EIS Engineering, Inc.                           |  | Delaware                 |  | 
|EIS Investments, LLC                            |  | Delaware                 |  | 
|ENEH Services, LLC                              |  | Delaware                 |  | 
|ETT Boston, Inc.                                |  | Delaware                 |  | 
|ETT Canada, Inc.                                |  | New Brunswick            |  | 
|ETT North America, Inc.                         |  | Delaware                 |  | 
|Exelon Allowance Management Company, LLC        |  | Delaware                 |  | 
|Exelon AOG Holding #1, Inc.                     |  | Delaware                 |  | 
|Exelon AOG Holding #2, Inc.                     |  | Delaware                 |  | 
|Exelon Business Services Company                |  | Pennsylvania             |  | 
|Exelon Capital Trust I                          |  | Delaware                 |  | 
|Exelon Capital Trust II                         |  | Delaware                 |  | 
|Exelon Capital Trust III                        |  | Delaware                 |  | 
|Exelon Communications Company, LLC              |  | Pennsylvania             |  | 
|Exelon Communications Holdings, LLC             |  | Delaware                 |  | 
|Exelon Corporation                              |  | Pennsylvania             |  | 



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|                                                        |  |                          |  |                                  
|------------------------------------------------------- |  | ------------------------ |  | ---------------------------------
|Affiliates                                              |  | Jurisdiction ofFormation |  |                                  
|Exelon Edgar, LLC                                       |  | Delaware                 |  |                                  
|Exelon Energy Company                                   |  | Delaware                 |  |                                  
|Exelon Energy Delivery Company, LLC                     |  | Delaware                 |  |                                  
|Exelon Enterprises Company, LLC                         |  | Pennsylvania             |  |                                  
|Exelon Enterprises Investments, Inc.                    |  | Delaware                 |  |                                  
|Exelon Enterprises Management, Inc.                     |  | Pennsylvania             |  |                                  
|Exelon Framingham Development, LLC                      |  | Delaware                 |  |                                  
|Exelon Framingham, LLC                                  |  | Delaware                 |  |                                  
|Exelon Generation Company, LLC                          |  | Pennsylvania             |  |                                  
|Exelon Generation Consolidation, LLC                    |  | Nevada                   |  |                                  
|Exelon Generation Finance Company, LLC                  |  | Delaware                 |  |                                  
|Exelon Generation International, Inc.                   |  | Pennsylvania             |  |                                  
|Exelon Hamilton LLC                                     |  | Delaware                 |  |                                  
|Exelon Investment Holdings, LLC                         |  | Illinois                 |  |                                  
|Exelon New Boston, LLC                                  |  | Delaware                 |  |                                  
|Exelon New England Development, LLC                     |  | Delaware                 |  |                                  
|Exelon New England Holdings, LLC                        |  | Delaware                 |  |                                  
|Exelon New England Power Marketing, Limited Partnership |  | Delaware                 |  |                                  
|Exelon Peaker Development General, LLC                  |  | Delaware                 |  |                                  
|Exelon Peaker Development Limited, LLC                  |  | Delaware                 |  |                                  
|Exelon PowerLabs, LLC                                   |  | Pennsylvania             |  |                                  
|Exelon Services, Inc.                                   |  | Delaware                 |  |                                  
|Exelon SHC, Inc.                                        |  | Delaware                 |  |                                  
|Exelon Synfuel I, LLC                                   |  | Delaware                 |  |                                  
|Exelon Synfuel II, LLC                                  |  | Delaware                 |  |                                  
|Exelon Synfuel III, LLC                                 |  | Delaware                 |  |                                  
|Exelon Thermal Development, Inc.                        |  | Delaware                 |  |                                  
|Exelon Thermal Holdings, Inc.                           |  | Delaware                 |  |                                  
|Exelon Ventures Company, LLC                            |  | Delaware                 |  |                                  
|Exelon West Medway Development, LLC                     |  | Delaware                 |  |                                  
|Exelon West Medway Expansion, LLC                       |  | Delaware                 |  |                                  
|Exelon West Medway, LLC                                 |  | Delaware                 |  |                                  
|Exelon Wyman, LLC                                       |  | Delaware                 |  |                                  
|ExRES Power Holdings, Inc.                              |  | Delaware                 |  |                                  
|EXRES SHC, Inc.                                         |  | Delaware                 |  |                                  
|ExTel Corporation, LLC                                  |  | Delaware                 |  |                                  
|ExTex LaPorte Limited Partnership                       |  | Texas                    |  | Trading as: Exelon Power Texas   
|ExTex Marketing, LLC                                    |  | Delaware                 |  |                                  
|ExTex Power, LP                                         |  | Delaware                 |  |                                  
|ExTex Retail Services Company, LLC                      |  | Delaware                 |  | Trading as: Exelon Power Services
|F & M Holdings Company LLC                              |  | Delaware                 |  |                                  
|Fischbach and Moore Electric, Inc.                      |  | Delaware                 |  |                                  
|Fischbach and Moore Electrical Contracting, Inc.        |  | Delaware                 |  |                                  
|Fischbach and Moore, Inc.                               |  | New York                 |  |                                  
|Horizon Energy Company                                  |  | Pennsylvania             |  |                                  
|II Services, Inc.                                       |  | Delaware                 |  |                                  
|Infrasource Field Services, LLC                         |  | Oklahoma                 |  |                                  
|La Salle 1 NQF, LLC                                     |  | Nevada                   |  |                                  
|La Salle 2 NQF, LLC                                     |  | Nevada                   |  |                                  
|Limerick I NQF, LLC                                     |  | Nevada                   |  |                                  



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|                                                |  |                          |  | 
|----------------------------------------------- |  | ------------------------ |  | 
|Affiliates                                      |  | Jurisdiction ofFormation |  | 
|Limerick 2 NQF, LLC                             |  | Nevada                   |  | 
|NEWCOSY, Inc.                                   |  | Delaware                 |  | 
|NEWCOTRA, Inc.                                  |  | Delaware                 |  | 
|North America Power Services, Inc.              |  | Delaware                 |  | 
|Northwind Boston, LLC                           |  | Massachusetts            |  | 
|Northwind Thermal Technologies Canada Inc.      |  | New Brunswick            |  | 
|Nuclear US Holdings, Inc.                       |  | Delaware                 |  | 
|Nuclear US Investments, LLC                     |  | Delaware                 |  | 
|Nuclear, Limited Partnership                    |  | Delaware                 |  | 
|NuStart Energy Development Management Committee |  | Delaware                 |  | 
|NuStart Energy Development, LLC                 |  | Delaware                 |  | 
|OldcoVSI, Inc.                                  |  | Delaware                 |  | 
|OSP Servicios, S.A. de C.V.                     |  | Mexico                   |  | 
|Peach Bottom I NQF, LLC                         |  | Nevada                   |  | 
|Peach Bottom 2 NQF, LLC                         |  | Nevada                   |  | 
|Peach Bottom 3 NQF, LLC                         |  | Nevada                   |  | 
|PEC Financial Services, LLC                     |  | Pennsylvania             |  | 
|PECO Energy Capital Corp.                       |  | Delaware                 |  | 
|PECO Energy Capital Trust III                   |  | Delaware                 |  | 
|PECO Energy Capital Trust IV                    |  | Delaware                 |  | 
|PECO Energy Capital Trust V                     |  | Delaware                 |  | 
|PECO Energy Capital Trust VI                    |  | Delaware                 |  | 
|PECO Energy Capital, LP                         |  | Delaware                 |  | 
|PECO Energy Company                             |  | Pennsylvania             |  | 
|PECO Energy Power Company                       |  | Pennsylvania             |  | 
|PECO Energy Transition Trust                    |  | Delaware                 |  | 
|PECO Wireless, LP                               |  | Delaware                 |  | 
|Penesco Company, LLC                            |  | Delaware                 |  | 
|PHT Holdings, LLC                               |  | Delaware                 |  | 
|Port City Power, LLC                            |  | Delaware                 |  | 
|Quad Cities 1 NQF, LLC                          |  | Nevada                   |  | 
|Quad Cities 2 NQF, LLC                          |  | Nevada                   |  | 
|Rand-Bright Corporation                         |  | Wisconsin                |  | 
|Salem I NQF, LLC                                |  | Nevada                   |  | 
|Salem 2 NQF, LLC                                |  | Nevada                   |  | 
|Scherer Holdings 1, LLC                         |  | Delaware                 |  | 
|Scherer Holdings 2, LLC                         |  | Delaware                 |  | 
|Scherer Holdings 3, LLC                         |  | Delaware                 |  | 
|Sithe Energies, Inc.                            |  | Delaware                 |  | 
|Sithe Energy Management Services II, Inc.       |  | Delaware                 |  | 
|Sithe Energy Management Services, Inc.          |  | Delaware                 |  | 
|Sithe International Finance II, LLC             |  | Delaware                 |  | 
|Sithe International Finance, LLC                |  | Delaware                 |  | 
|Sithe International, Inc.                       |  | Delaware                 |  | 
|Sithe Latin America Holdings, Ltd.              |  | Cayman Islands           |  | 
|Sithe Overseas Power Services, Ltd.             |  | Virgin Islands           |  | 
|Sithe Pardo Holdings, Ltd.                      |  | Cayman Islands           |  | 



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|                                                    |  |                          |  | 
|--------------------------------------------------- |  | ------------------------ |  | 
|Affiliates                                          |  | Jurisdiction ofFormation |  | 
|Sithe Tamuin Energy Services II, S. de R.L. de C.V. |  | Mexico                   |  | 
|Sithe Tamuin Energy Services, S. de R.L. de CV.     |  | Mexico                   |  | 
|Sithe Tamuin Holdings A, LLC                        |  | Delaware                 |  | 
|Sithe Tamuin Holdings, LLC                          |  | Delaware                 |  | 
|Sithe Tamuin Holdings II, LLC                       |  | Delaware                 |  | 
|Sithe Tamuin Holdings III, LLC                      |  | Delaware                 |  | 
|Sithe Tamuin Investments II, S. de R.L. de C.V.     |  | Mexico                   |  | 
|Sithe Tamuin Investments, S. de R.L. de C.V.        |  | Mexico                   |  | 
|Southeast Chicago Energy Project, LLC               |  | Delaware                 |  | 
|Spruce Equity Holdings, LP                          |  | Delaware                 |  | 
|Spruce Holdings G.P. 2000, LLC                      |  | Delaware                 |  | 
|Spruce Holdings L.P. 2000, LLC                      |  | Delaware                 |  | 
|Spruce Holdings Trust                               |  | Delaware                 |  | 
|Susquehanna Electric Company                        |  | Maryland                 |  | 
|Susquehanna Power Company                           |  | Maryland                 |  | 
|Tamuin Development Services de R.L. de C.V.         |  | Mexico                   |  | 
|Tamuin Mexican Business Trust                       |  | Mexico                   |  | 
|Tamuin Mexican Business Trust II                    |  | Mexico                   |  | 
|T.H. Green Electric Co., Inc.                       |  | New York                 |  | 
|TEG Holdings, LLC                                   |  | Delaware                 |  | 
|Termoelectrica Del Golfo S. de R.L. de C.V.         |  | Mexico                   |  | 
|Termoelectrica Penoles S. de R.L. de C.V.           |  | Mexico                   |  | 
|Texas Ohio Gas, Inc.                                |  | Texas                    |  | 
|The Proprietors of the Susquehanna Canal            |  | Maryland                 |  | 
|UII, LLC                                            |  | Illinois                 |  | 
|Unicom Assurance Company, Ltd.                      |  | Bermuda                  |  | 
|Unicom Power Marketing Inc.                         |  | Delaware                 |  | 
|UniGridEnergy, LLC                                  |  | Delaware                 |  | 
|URI, LLC                                            |  | Illinois                 |  | 
|Wansley Holdings 1, LLC                             |  | Delaware                 |  | 
|Wansley Holdings 2, LLC                             |  | Delaware                 |  | 
|Zion I NQF, LLC                                     |  | Nevada                   |  | 
|Zion 2 NQF, LLC                                     |  | Nevada                   |  |