| Alabama Power |
| Allegheny Energy Supply |
| Alstom Power, Inc. |
| American Electric Power |
| Army Corp of Engineers |
| Calpine |
| Denver City Energy |
| Duke Energy |
| Dynegy |
| EME/Midwest Generation |
| First Energy |
| GPU Energy |
| Keyspan Energy |
| LVI Environmental Systems |
| PPG Industries, Inc. |
| PPL Montana |
| PacifiCorp |
| Portland General Electric |
| Reliant Energy |
| Tillamook PUD |
| TransAlta |
