| 3M Company |
| A. Finkl & Sons Co. |
| Abbott |
| Abbott Laboratories |
| ACES Power Marketing |
| Advanced Power |
| AEP |
| Ag Energy Co-op |
| AGL Resources |
| Air Liquide Canada Inc. |
| AK Steel Corp |
| Alabama Gas Corp. |
| Albany Water, Gas & Light Commission |
| Alliant Energy |
| Alstyle Apparel |
| Amaizeingly Green Products, L.P. |
| Ameren |
| American Electric Power |
| American Public Gas Association |
| Appalachian Natural Gas Distribution |
| Arcelor Mittal USA |
| ARM Services |
| Asphalt Materials |
| ATCO Noise Management |
| Atmos Energy Corporation |
| Aux Sable Canada Ltd. |
| Avista Corp |
| Aviva |
| Bangor Gas Company, LLC. |
| Baxter Healthcare Corporation |
| Bay State Gas Company |
| Berkshire Gas Co. |
| Black Hills Energy |
| Bmark Energy |
| Boise Inc. |
| Bombardier Inc. |
| Bon L Aluminum |
| Boston Generating Services |
| BOYD Consulting |
| Bridgeport Utilities |
| Brookfield Asset Management |
| BTU Acquistions Ltd. |
| Bucksport Energy LLC |
| Burbank Water & Power |
| California Dairies, Inc. |
| California State University-Dominguez Hills |
| Calpine Energy Services |
| Cargill |
| Cascades Inc. |
| CenterPoint Energy |
| Centra Gas Manitoba Inc. (subsidiary of Manitoba Hydro) |
| Central Hudson Gas & Electric |
| CertainTeed Insulation Canada/Ottawa Fibre L.P. |
| CF Industries Inc. |
| CH Energy Group, Inc. |
| Chicago Housing Authority |
| Citizens Energy Group |
| City of Central City, Nebraska |
| City of Cerritos |
| City of Chicago |
| City of Florence Gas & Water |
| City of Glendale |
| City of Hamilton |
| City of Lakeland |
| City of Long Beach |
| City of Pasadena |
| City of Roseville/Roseville Electric |
| City of Safford |
| City of Sugar Hill |
| City of Tallahassee |
| City of Vernon |
| City of Victorville |
| Clarke-Mobile Counties Gas District |
| Clayton Energy |
| CNG & SCG |
| Cokinos Energy Corporation |
| Collingwood Ethanol L.P. |
| Colorado Springs Utilities |
| Commodity Risk Management L.P. |
| Competitive Energy Services |
| Conectiv Energy |
| Constellation NewEnergy Gas Division |
| Consultant |
| Consumers Energy |
| Corinth Gas & Water |
| Corn Products International |
| Cornell University |
| Covidien |
| CT Natural Gas / The Southern CT Gas Company |
| Deere & Company |
| Delta Energy llc |
| Direct Energy |
| Diversified Energy Supply |
| Dominion |
| DTE Energy - MichCon |
| Duke Energy |
| Dynegy |
| Dyno Nobel Inc. |
| Early Bird Power |
| ECG, LLC |
| Eco Clean Energy, Inc. |
| Edison |
| Emera Energy Inc |
| Enbridge Gas Distribution Inc. |
| Energetix/NYSEG Solutions |
| Energy Atlantica Ltd. |
| Energy Management Resources |
| Energy New England |
| Energy Solutions/FireSide Natural Gas |
| Energy West |
| Enmax |
| Enpower Corp. |
| EQT Energy, LLC |
| Etowah Utilities |
| Exelon Energy |
| Exelon Generation |
| Federal Express |
| FERC |
| Fitchburg Gas & Electric Light |
| Florida Gas Utility |
| Florida Municipal Power Agency |
| Florida Power & Light |
| Fontana Paper Mills |
| Fountain Inn Natural Gas |
| Four Seasons Site Development |
| FPL |
| Gas South |
| Gaz Metro |
| GELITA USA - Chicago |
| GELITA USA - Sioux City |
| GenPower Holdings, LLC |
| Georgia-Pacific |
| Global Companies |
| Goodrich Corporation |
| Greenville Utilities Commission |
| Greer Commission of Public Work |
| Grifols |
| Guardian Industries Corp. |
| Hawkins County Gas Utility |
| Henderson Municipal Gas |
| Hilton Worldwide |
| Holcim (US) Inc. |
| Holyoke Gas and Electric |
| Huntsville Utilities |
| Hydro-Quebec |
| Idaho Power |
| IGS Energy |
| Imperial Irrigation District |
| Indeck Energy Services, Inc. |
| Ineos Nova Ltd |
| Ingram Asphalt Inc |
| Integrys |
| Integrys Gas Group |
| Intermountain Gas Company |
| International Power America |
| Interstate Brands Corp. |
| Invenergy LLC |
| Irving Oil Limited |
| James Smallwood Consulting |
| Kansas Gas Service |
| Kimberly-Clark Corporation |
| Kleen Energy Systems, LLC |
| Kronos Canada, Inc |
| Kruger Inc. |
| Lanxess Inc |
| Long Beach Gas & Oil Department |
| Los Angeles Department of Water and Power |
| Los Angeles Dept. of Water and Power |
| Loudon Utilities |
| LSB Industries, Inc. |
| MA Dept of Telecom & Energy |
| Madison Gas and Electric Company |
| Magnolia Power Project |
| Marathon Oil |
| Marion Natural Gas |
| Massachusetts DPU |
| McCain Foods USA |
| MeadWestvaco |
| MEAG Power |
| Memphis Light, Gas & Water |
| Metropolitan Utilities District |
| Middle Tennessee Natural Gas |
| Middleborough Gas & Electric Dept. |
| Minnesota Energy Resources |
| MIRANT |
| Mirant Corporation |
| Mirant Energy Corporation |
| Mission Foods Corporation |
| Missouri Gas Energy |
| Mitsubishi Cement Corporation |
| Mobile Gas Service Corp. |
| Mobius Risk Group |
| Montana-Dakota Utilities |
| Municipal Gas Authority of Georgia |
| Municipal Gas Authority of MS (MGAM) |
| MuniGas |
| National Fuel Gas Company |
| National Fuel Resources Inc. |
| National Grid |
| Nestle USA |
| New Hampshire Public Utilities |
| NextEra |
| Nicor Gas |
| Nipsco |
| NiSource Energy technolgies |
| NJ Natural Gas Co. |
| NJR Energy Services Co. |
| North Alabama Gas District |
| North American Stainless |
| North Carolina Municipal Power Agency |
| Northeast Gas Association |
| Northern Indiana Energy |
| Northern Indiana Public Service Co. |
| Northwest Alabama Gas District |
| Northwest Natural Gas |
| Nova Scotia Power |
| NRG Energy, Inc. |
| NSTAR |
| NV Energy |
| NW Natural |
| Oglethorpe Power Corp |
| O-I |
| Okaloosa Gas District |
| Old Town Fuel & Fiber |
| Omnitrans |
| Oregon Public Utiltiy Commission |
| Ouff Eenterprises Pvt Ltd. |
| Owl Energy Resources, Inc. |
| Packaging Corporation of America |
| Panda Energy |
| PepsiCo, Inc. |
| Pfizer |
| PG&E |
| PG&E Electric Fuels Management |
| Piedmont Natural Gas Co. |
| Pilkington North America, Inc. |
| Pioneer Valley Energy Center |
| Portland General Electric |
| Portlands Energy Centre |
| Potash Corp. |
| Potash Corp. of Saskatchewan |
| Powerex Corp. |
| PowerSouth Energy Cooperative |
| PPL EnergyPlus |
| Pratt Industries |
| Prenova |
| Procter & Gamble Co. |
| Progress Energy |
| ProLiance Energy, LLC |
| PSE&G |
| Public Energy Authority of Kentucky |
| Puget Sound Energy |
| Purdue University |
| Questar Gas Company |
| Rainbow Energy Marketing Corporation |
| Redding Electric Utility |
| Rockwood Gas System |
| RRI Energy Services, Inc. |
| RSCM Energy |
| Sacramento Municipal Utility District |
| Safeway |
| San Diego Gas & Electric Co. |
| Saputo |
| SaskEnergy |
| Scana Energy Marketing |
| SCE |
| SDG&E |
| SEGAS |
| SEMCO Energy |
| Semco Energy Gas Company |
| Sempra Generation |
| Sempra Solutions |
| Sevier County Utility District |
| Siemens Building Technologies |
| SLH, LLC |
| Smurfit-Stone Container |
| Smurfit-Stone Container Corp |
| SNGPL |
| SoCalGas/SDG&E |
| Solar Turbines Incorporated |
| South Jersey Gas Co. |
| South Mississippi Electric |
| Southeast Alabama Gas District |
| Southen California Gas Co. |
| Southern California Gas |
| Southern Company |
| Southern Connecticut Gas Co. |
| SouthStar Energy Services, LLC |
| Southwest Gas Corporation |
| Spark Energy Gas L.P |
| Spectra Energy |
| Springfield Gas System |
| State of Illinois |
| Stepan Company |
| StrataPower |
| Stream Energy |
| Subaru of Indiana Automotive |
| Sunoco Inc. |
| Swisstex California Inc. |
| TAS Asscoiates/Bay State Gas |
| Taunton Municipal Light Plant |
| TECO |
| Tembec |
| Tennessee Valley Authority |
| Terasen Gas Inc. |
| Terra Industries |
| The Energy Authority |
| TIMCO |
| TransCanada |
| Trigen |
| Tyson Foods, Inc. |
| U. S. Steel Canada Inc. |
| U.S. Energy Services, Inc. |
| UGI Utilities Inc. |
| Union Gas Limited |
| United Cogen |
| United Dairymen of Arizona |
| United Energy/Rainbow Energy Marketing |
| United States Gypsum Co. |
| Unitil |
| USG Corporation |
| USSteel |
| Vectren Retail, LLC |
| Vermont Gas Systems, Inc. |
| Verso Paper LLC |
| VIA Rail |
| Ville De Montreal |
| Vulcan Materials Co. |
| Wal-Mart Stores Inc. |
| Washington Gas Light Company |
| We-Energies |
| Welch's Company |
| Westar Energy |
| Xstrata Copper Canada |
| Xstrata Nickel |
| Yaka Energy |
| Yankee Candle Company |
| Yankee Gas Services Company |
| York County Natural Gas Authority |
