EPC (Engineering, Procurement, and Construction) Contractor

An EPC contractor handles all three phases of a solar project: Engineering (system design and permitting), Procurement (sourcing panels, inverters, and other equipment), and Construction (physical installation and commissioning). EPC contractors provide a complete, end-to-end solar installation service.

In the residential solar market, most solar companies operate as EPC contractors — they design your system, purchase the equipment, install the panels, handle permitting and inspections, and coordinate the utility interconnection. The EPC model gives homeowners a single point of contact and accountability for the entire project. In the commercial and utility-scale solar market, the EPC contractor role is more formally defined and often involves separate contracts for each phase. When evaluating solar companies, choosing one that handles all EPC functions in-house (rather than subcontracting) generally results in better quality control, faster timelines, and clearer warranty coverage. Key questions to ask an EPC: Do you use in-house installation crews or subcontractors? Who handles the permitting and utility paperwork? What does your workmanship warranty cover?