Exhibit 21 | ||||||||
Affiliates and Subsidiaries of Integrys Energy Group, Inc. December 31, 2007 | ||||||||
| INTEGRYS ENERGY GROUP, INC.+ * | ||||||||
| Wisconsin Public Service Corporation+ | ||||||||
| WPS Leasing, Inc.+ | ||||||||
| Wisconsin Valley Improvement Company (27.1% ownership) + | ||||||||
| Wisconsin River Power Company (50% ownership)+ | ||||||||
| WPS Investments, LLC (approximately 17.3% ownership)+ | ||||||||
| American Transmission Company LLC (approximately 34.54% ownership)+ | ||||||||
| ATC Management Inc. (32.58% ownership)+ | ||||||||
| WPS Investments, LLC (approximately 77.93% ownership)+ | ||||||||
| American Transmission Company LLC (approximately 34.54% ownership)+ | ||||||||
| WPS Nuclear Corporation+ | ||||||||
| Michigan Gas Utilities Corporation++ | ||||||||
| Minnesota Energy Resources Corporation++ | ||||||||
| Integrys Business Support, LLC++ | ||||||||
| WPS Visions, Inc.+ | ||||||||
| Badger Energy Services, LLC (12.50% ownership)+ | ||||||||
| Integrys Energy Services, Inc.+ | ||||||||
| Quest Energy, LLC+++ | ||||||||
| Integrys Energy Services of Canada Corp. (formed under Canadian law) | ||||||||
| Integrys Energy Services of New York, Inc. (formed under New York law) | ||||||||
| Integrys Energy Services of Texas, LP (formed under Texas law) | ||||||||
| PERC Holdings, LLC++ | ||||||||
| WPS Power Development, LLC+ | ||||||||
| PDI Stoneman, Inc.+ | ||||||||
| Mid-American Power, LLC+ | ||||||||
| Winnebago Energy Center, LLC++ | ||||||||
| WPS Canada Generation, Inc.+ | ||||||||
| WPS New England Generation, Inc.+ | ||||||||
| Wisconsin Woodgas LLC+ | ||||||||
| Wisconsin Energy Operations LLC (49% ownership)+ | ||||||||
| ECO Coal Pelletization #12 LLC (70% ownership)++ | ||||||||
| Synfuel Solutions, LLC (33.33% ownership)++ | ||||||||
| Synfuel Solutions Operating, LLC++ | ||||||||
| Sunbury Holdings, LLC++ | ||||||||
| WPS Westwood Generation, LLC++ | ||||||||
| WPS Empire State, Inc. (formed under New York law) | ||||||||
| WPS Beaver Falls Generation, LLC++ | ||||||||
| WPS Syracuse Generation, LLC++ | ||||||||
| Combined Locks Energy Center, LLC+ | ||||||||
| PV Midstream Ventures, LLC (50% ownership)++ | ||||||||
| Peoples Natural Gas Liquids, LLC++ | ||||||||
Affiliates and Subsidiaries of Integrys Energy Group, Inc. December 31, 2007 | ||||||||
| INTEGRYS ENERGY GROUP, INC.+* | ||||||||
| Peoples Energy Corporation++++ | ||||||||
| The Peoples Gas Light and Coke Company++++ | ||||||||
| Peoples Gas Neighborhood Development Corporation++++ | ||||||||
| North Shore Gas Company++++ | ||||||||
| Peoples Energy Services Corporation++++ | ||||||||
| Peoples Energy Resources Company, LLC++ | ||||||||
| Peoples MW, LLC++ | ||||||||
| PERC Power, LLC++ | ||||||||
| Peoples Elwood, LLC++ | ||||||||
| Elwood Energy, LLC (50% ownership)++ | ||||||||
| Peoples District Energy Corporation++++ | ||||||||
| Peoples Energy Ventures, LLC++ | ||||||||
| Peoples Energy Home Services, LLC++ | ||||||||
| Peoples Energy Neighborhood Development, LLC++ | ||||||||
| Peoples Technology, LLC++ | ||||||||
| Upper Peninsula Power Company+++ | ||||||||
| WPS Investments, LLC (approximately 4.76% ownership)+ | ||||||||
| American Transmission Company LLC (approximately 34.54% ownership)+ | ||||||||
| ATC Management Inc. (1.96% ownership)+ | ||||||||
| Upper Peninsula Building Development Company+++ | ||||||||
| Penvest, Inc.+++ | ||||||||
| * | Integrys Energy Group, Inc. is the parent holding company. All affiliated companies listed are 100% owned except as noted otherwise. All affiliates are currently active, with the exception of Wisconsin Woodgas, LLC, Synfuel Solutions, LLC, and (checking on PEC companies). | |||||||
| + | Formed under Wisconsin law | |||||||
| ++ | Formed under Delaware law | |||||||
| +++ | Formed under Michigan law | |||||||
| ++++ | Formed under Illinois law | |||||||