15KW Complete Offgrid Solar Kit + EG4 FlexBOSS21 + 2x 14.3KW 48V EG4 Lithium Indoor Wall Battery + 15.4KW Solar with Roof Mounting Rails and Wiring

The 15KW Complete Offgrid Solar Kit + EG4 FlexBOSS21 + 2x 14.3KW 48V EG4 Lithium Indoor Wall Battery + 15.4KW Solar with Roof Mounting Rails and Wiring  is designed for dependable whole-home off-grid power. It pairs a 15.4kW bifacial solar array with the versatile EG4 FlexBOSS21 48V split-phase hybrid inverter/charger and 28.6kWh of usable lithium storage from two 14.3kWh EG4 indoor wall batteries. Producing about 69,300 watts per day at 4.5 peak sun hours, this expandable system is a strong fit for mid-sized homes using ~2,000 kWh per month and can scale with added panels or batteries as your needs grow.

Specifications

• Solar Array: 28 × 550W bifacial mono double-glass panels (15,400W total)

• Inverter/Charger: EG4 FlexBOSS21 — 48V split-phase, hybrid inverter/charger

• Battery Storage: (2) × 14.3kWh 48V EG4 Lithium Indoor Wall Batteries (28.6kWh usable)

• Roof Mount System: Complete IronRidge rails, splices, legs, fasteners, and bolts

• Balance of System: Solar combiner box, gutter box, Anderson plug battery cable set, 500' 10AWG PV direct-burial wire, 100' 6AWG AC cabling, MC4 crimp kit, installation manual

Features

• Bifacial Energy Gain: Up to ~25% rear-side harvest; stronger output in low-light (cloudy, hazy, early morning)

• High Durability Panels: 5400Pa snow load & 2400Pa wind load; 30-year power warranty

• Application Ready: Ideal for small cabins, RVs, garages, pole barns, and full off-grid homes; runs everyday essentials

• Appliance Support: Well pump, washing machine, fans, TVs, lights, refrigerator, freezer, phones/PCs/tablets, smaller AC systems

• Expandable Architecture: Add more panels or batteries anytime; BOS and inverter designed for growth

• DIY-Friendly Install: Homeowners with basic wiring skills can install; roof-mount racking is typically the most labor-intensive step

Maintenance

• Daily: Monitor inverter/battery status; keep modules free of debris/shading

• Weekly: Visual check of wiring, mounts, and production versus expected sun hours (~4.5 hrs Midwest)

• Annually: Re-torque roof hardware, clean panels thoroughly, and inspect all electrical connections

Warranty

• Solar Panels: 30-year power output warranty

• Inverter & Batteries: Covered under EG4 manufacturer warranties