| A-TEC Energy | 2011 |
| Ameren Illinois | 2010 |
| American Council for an Energy-Efficient Economy (ACEEE) | 2000 |
| American Efficient | 2018 |
| Applied Energy Group | 2019 |
| APTIM | 2010 |
| Argonne National Laboratory | 2011 |
| Bradford White Corporation | 2019 |
| Cadmus | 2004 |
| Cascade Energy | 2017 |
| Celia Johnson Consulting | 2018 |
| CenterPoint Energy | 2004 |
| Chicago Bungalow Association | 2018 |
| City of Chicago | 2004 |
| City Water, Light & Power | 2007 |
| CLEAResult | 2013 |
| CMC Energy Services | 2018 |
| Combined Heat and Power Alliance | 2014 |
| Commonwealth Edison | 2000 |
| Consumers Energy | 2010 |
| D+R International | 2011 |
| Daikin North America LLC | 2019 |
| DNV GL | 2005 |
| DTE Energy | 2009 |
| E Source | 2010 |
| Edison Foundation Institute for Electric Innovation | 2009 |
| Elevate Energy | 2017 |
| Emerson Commercial & Residential Solutions | 2019 |
| Energy Insight, Inc. | 2015 |
| Erthe Energy Solutions | 2018 |
| Evergreen Consulting Group | 2018 |
| EZ Green Home | 2019 |
| Franklin Energy | 2008 |
| Frontier Energy | 2017 |
| Fujitsu General America, Inc. | 2014 |
| Future Energy Enterprises, LLC | 2009 |
| Geothermal Alliance of Illinois | 2011 |
| Greenlite | 2019 |
| GTI | 2017 |
| Honeywell Smart Grid Solutions | 2014 |
| ICF | 2000 |
| Illinois EPA | 2017 |
| Ingersoll Rand | 2017 |
| Itron, Inc. | 2009 |
| JadeTrack | 2019 |
| Leidos | 2010 |
| Lennox Industries | 2018 |
| Lime Energy | 2012 |
| Lockheed Martin | 2009 |
| MaxLite | 2018 |
| Michigan Agency for Energy - Michigan Energy Office | 2006 |
| Michigan Saves | 2018 |
| Mid-West Energy Research Consortium (M-WERC) | 2015 |
| MidAmerican Energy Company | 2006 |
| Missouri Botanical Garden's EarthWays Center | 2009 |
| Mitsubishi Electric Trane HVAC US LLC | 2010 |
| Morgan Marketing Partners | 2010 |
| National Energy Foundation | 2015 |
| Navigant Consulting, Inc. | 2003 |
| Nest | 2015 |
| Nexant, Inc. | 2010 |
| Nicor Gas | 2012 |
| North Shore Gas | 2010 |
| Northwest Energy Efficiency Council (NEEC) | 2008 |
| NTC | 2014 |
| Oracle Utilities | 2010 |
| PACENation | 2018 |
| Peoples Gas | 2010 |
| Performance Systems Development (PSD) | 2018 |
| Philips Lighting | 2012 |
| Power TakeOff, Inc. | 2017 |
| Powerley | 2018 |
| Resource Action Programs | 2012 |
| Resource Innovation Institute | 2019 |
| Resource Innovations | 2016 |
| SEMCO Energy Gas Company | 2014 |
| Sodexo | 2017 |
| Staples Energy | 2008 |
| Technical Consumer Products, Inc. | 2005 |
| The National Energy Improvement Fund (NEIF) | 2015 |
| Upper Peninsula Power Company | 2019 |
| VEIC | 2015 |
| Village of Oak Park | 2018 |
| Wabash Valley Power Association | 2004 |
| Walker-Miller Energy Services | 2019 |
| Waypoint | 2017 |
| We Energies | 2019 |
| West Monroe Partners | 2014 |
| Willdan | 2001 |
| Wisconsin Public Service | 2019 |
| WPPI Energy | 2018 |
| Xcel Energy | 2000 |
