Here's a realistic phase-by-phase look at what a professional solar (and, if included, battery) installation actually involves.

Phase 1: Site Assessment and System Design

A proper installation starts with an assessment of roof condition, orientation, shading, and your actual electricity usage from utility bills. This phase should produce a proposed system size, expected production estimate, and a firm quote — not just an assumed standard system size applied to every home.

Phase 2: Permitting

Solar installations require permits from the local jurisdiction and a formal interconnection application with your utility company. This phase typically takes several weeks and happens before physical installation begins — a step that's easy to underestimate when planning a project timeline.

Phase 3: Installation

Panels, mounting hardware, inverters, and (if included) battery equipment get physically installed. This is typically the fastest phase of the overall project, often completed within a few days once permits are approved, though roof condition and system size affect the actual timeline.

Phase 4: Inspection

A local building inspector and, separately, the utility company typically both need to inspect and approve the installation before the system can be legally activated and connected to the grid — a required step, not an optional formality.

Phase 5: Utility Interconnection and Activation

Once inspections pass, the utility company completes interconnection and the system is formally activated. This is the point at which net metering (if applicable) begins, and the system starts actually offsetting grid electricity usage.

Phase 6: Monitoring Setup and Training

A proper installation includes setting up production monitoring (typically through an app) and walking through how to interpret it, what a normal range of daily production looks like for your system, and who to contact if production drops unexpectedly.

What a Written Scope Should Include

  • System size and expected annual production estimate, based on your actual usage and roof-specific factors.
  • Equipment brand and model for panels, inverters, and batteries if included.
  • Permitting and interconnection timeline, factored into the overall project schedule.
  • Warranty terms for equipment and workmanship separately.

Realistic Timelines

From signed contract to system activation, a typical residential solar project takes 2-4 months total, with permitting and utility interconnection accounting for much of that time rather than the physical installation itself, which is usually the fastest phase.