- Ameron/Cilco Medina
- Arkansas Kraft
- British Petroleum
- CalPine
- CalPine Metcalf
- Choctaw Gas Generation
- Demarva Power
- Duke Energy
- Dupont
- Effington County
- Energy Northwest
- General Electric
- Houston Light & Power
- Indiana Power
- Nebraska Power
- Northern States Power
- Nooter Erikson
- Novacor Chemical Ltd
- Oneta Corporation
- Proctor and Gamble
- Progress Energy
- PSEG Power NY
- Reliant Energy
- Shell Chemical
- Trans Alta
- US Air Force
- US Coast Guard
- US Navy
- Veolia Water Co
- XCEL Energy