EPC (Engineering, Procurement, and Construction)
Also known as: Turnkey Contractor, Turnkey Provider
A contract form — not a technical function — under which a single entity takes full responsibility for engineering, procuring, and constructing a complete BESS plant. The EPC contractor bears commercial accountability for performance, schedule, and cost. Under an EPC contract, the EPC contractor coordinates all equipment interfaces and delivers the plant as a working system.
In energy storage
EPC is not the only delivery model. Developers with sufficient technical capability can bypass the EPC wrapper entirely by procuring equipment directly — buying DC blocks, PCS, controls, and other components from separate suppliers. In doing so, the developer takes on responsibility for coordinating equipment interfaces and delivering a compliant plant. The technical coordination is the same regardless of who holds it commercially; the difference is contractual structure and risk allocation.