| Company | City | Service Type | Products |
| American Sun Electric | Blue Hill | Residential, | Solar Electric (pv), |
| American Sun Electric.inc | Blue Hill | Residential, | Solar Electric (pv), |
| Assured Solar Energy | North Yarmouth | Residential, ,Commercial, ,Municipal, | Solar Electric (pv), Solar Hot Water (thermal), Solar Pool Heating, |
| Goggin Energy | Portland | ||
| Heliotropic Technologies | Boothbay Harbor | Residential, | Solar Electric (pv), |
| Insource Renewables | Pittsfield | Residential, | Solar Electric (pv), |
| Integrated Energy Systems, PLLC | Falmouth | Commercial, | Solar Electric (pv), |
| Midcoast Energy Systems, Inc. | Damariscotta | Residential, | Solar Electric (pv), |
| Revision Energy | Liberty | Residential, | Solar Electric (pv), |
| Saco Solar | Saco | Residential, | Solar Electric (pv), |
| Solaris | Portland | Residential, Commercial, Municipal, | Solar Electric (pv), Solar Hot Water (thermal), Solar Pool Heating, |
