Below is a list of companies who attended Solar and Energy Storage SE 2021.
| A1a Solar |
| Accenture |
| Access Innovators |
| Advanced Energy |
| AEE Solar |
| AMEA |
| AP Alternatives, LLC |
| Apex Clean Energy |
| Avangrid Renewables |
| Bennett International Transport LLC |
| Beyond Solar |
| Blue Ridge Power |
| Bowman Consulting Group |
| Brent Scarbrough & Co |
| BroCo Solar |
| CAB Products |
| Canadian Solar |
| Capital Power Corporation |
| Carrick-Williams Companies |
| Certrec |
| CO2Efficient |
| Commonwealth Associates, Inc. |
| Convention Data Services |
| Crayhill Renewables |
| Credit Human |
| Diversified Power Inc. |
| DLV Associates, Inc. |
| Duke Energy |
| Ecker Construction, Inc. |
| EcoFasten |
| Electro-Mechanical Industries |
| Enteligent |
| Birdseye Renewable Energy |
| BL Harbert International |
| EN Engineering |
| Enercon Services, Inc. |
| Energy Assurance LLC |
| Energy Systems Southeast |
| Entergy Corporation |
| Equinor |
| Ferguson Waterworks |
| Filtrexx International |
| First Solar |
| Florida Solar & Air, Inc. |
| GDS Associates, Inc. |
| Generac Power Systems |
| Georgia Public Service Commission |
| GeothinQ |
| GoodWE USA Inc. |
| Graham Technical Sales, LLC |
| GrassWorx LLC |
| Green Power EMC |
| GreenFront Energy Partners |
| Gresco Utility Supply, Inc. |
| Grid Strategies LLC |
| HardHat Renewable Energy |
| HardHat Workforce Solutions, LLC |
| HDR Engineering, Inc. |
| Heliene |
| Honeywell International Inc. |
| Hospitality Energy LLC |
| Hypower, Inc. |
| Hyundai Energy Solutions America |
| IMO Automation |
| JinkoSolar (U.S.) Inc. |
| Jones Logistics |
| K2 Systems, LLC |
| Kimley-Horn and Associates, Inc. |
| Krannich Solar USA |
| Leyline Renewable Capital |
| Marston and Associates |
| Mecalfab Ltd. |
| Mission Solar Energy |
| Mitsubishi Electric Power Products, Inc. |
| Monarch Private Capital |
| Montrose Environmental Group |
| myPV |
| Neighborhood Microgrid Solutions |
| New Project Media |
| Nextera Energy |
| NLR Solar |
| Noahs Energy LLC |
| OMCO Solar |
| Orion GE |
| Palladium Energy, LLC |
| Parker Poe Adams & Bernstein, LLP |
| Peed Bros., Inc. |
| Polytech Services |
| Prime Engineering Incorporated |
| Pure Power Contractors Inc. |
| QuickBOLT |
| Radiance Solar |
| Ramluck |
| Raptor Maps |
| Renewable Sales and Power |
| Resitech Industries |
| Roof Tech |
| Semapro Group |
| Seminole Financial Services |
| Shree Vishnu Hotel LLC |
| Siemens |
| Sky Line Development |
| Sofos Harbert Renewable Energy |
| Solarology, LLC |
| Sonnen USA |
| Southern Alliance for Clean Energy (SACE) |
| SunPower Corporation |
| Sunshine Solar, LLC |
| SWCA Environmental Consultants |
| Tectonic |
| Tenger Finance |
| Tesla Owners Club of Arkansas |
| UKA North America, LLC |
| Utiklity Specialists, Inc. |
| Vermeer Corporation |
| Wattch |
| Wood PLC |
| WORD Rock Drills |
| Workrise |