Solar Project - Temecula, CA

This is a 17.2 kW DC / 24 kW AC solar + 48 kWh battery storage system for a single-family home in Temecula, CA 92592 (Riverside County). This is a DIY installation with a professionally prepared permit plan set. The system is designed as a whole-house battery backup with grid-tied capability ... no net meter, no grid backfeed ... routed through the existing 200A main panel on the south side of the house. I am planning to change this to include a sub-panel and move all branch circuits to it to have a whole home backup.

Utility → Meter → 200A Main Breaker → GridBOSS Grid-In → GridBOSS Backup Load Out → Sub-Panel (all branch circuits)

System Configuration

Solar Array: 43 SEG Solar SEG-400-BMD-HV panels (400W each) flush-mounted on a W-tile (clay tile) roof across south, east, and west orientations. The plan set shows two main arrays — Array 3 at 9.2 kW (23 modules, 170° azimuth) and Array 4 at 4.0 kW (10 modules, 80° azimuth), both at 18° tilt on a 4:12 pitch. Racking is IronRidge XR-10 rail with All Tile Hook attachments (114 total attachment points), installed on 2x4 trusses at 24" o.c. with 5/16" lag bolts at 2-1/2" embedment.

Inverters: Two EG4 FlexBOSS21 hybrid inverters (one already owned, one to purchase), each rated at 12 kW continuous / 24 kW peak. Three MPPT channels per unit, 600V max DC input, 240V split-phase AC output. These handle solar charging, battery management, and AC output.

Battery Bank: Three EG4 WallMount All Weather lithium batteries (48V / 314Ah each, ~16 kWh usable per unit = ~48 kWh usable total). Connected in parallel to the inverters with conduit boxes. Wall-mounted on the south exterior wall near the inverters.

Grid Interconnection: One EG4 GridBOSS MID V3.1 — this is the central hub that ties the two FlexBOSS inverters to the grid and the main panel. It serves as the service entrance device, replacing the need for separate transfer switches, combiners, and backfeed breakers. The full 200A bus runs through the GridBOSS back to the existing panel for whole-home backup capability. A single dedicated 15A PV backfeed breaker (CB3) connects at the main panel per CEC 705.12(A).

Rapid Shutdown: Tigo TS4-A-O module-level optimizers on each panel with a Cloud Connect Advanced (CCA) data logger and Tigo Access Point (TAP) for NEC 690.12 compliance. Two RSD initiation buttons and a DC isolator are shown on the plans.

Scope of Work — Electrician

ME: I am handling the solar panel installation, racking, Tigo rapid shutdown devices, roof conduit, and mounting all equipment (inverters, batteries, GridBOSS) myself to keep costs down. I would like to handle the permitting but do not know if that is possible. I am visiting the permitting office to discuss / review.

YOU: What I need help with is the electrical work — specifically installing the new sub-panel inside the garage, moving all existing branch circuits from the current main panel to the new sub-panel, and running all wiring and conduit between the main panel, GridBOSS, inverters, batteries, and sub-panel. I also need to add a new 60A circuit for a pool heat pump. The existing main panel has a 50A pool sub-panel feed that will also need to be relocated. I have the full permit plan set and equipment spec sheets available for review.

Here is just the sub-panel project:

https://iuse.page/kalman/projects/sub-panel

Partial Permit Plan Set for your review below: