There are three fundamentally different approaches to adding battery storage to a solar system. Each has distinct advantages, costs, and suitability for different situations.
Grid-Tied with Battery Backup
Battery bank stores excess solar production for use during grid outages. System still exports to grid when full.
Best for: Homeowners who want backup power during outages but also want to remain connected to the grid.
Pros: No blackout risk. Grid acts as infinite battery. Can sell excess solar back.
Cons: Complex system. Requires hybrid inverter. Higher cost than standard grid-tied.
Off-Grid System
Completely disconnected from the grid. 100% energy independence.
Best for: Remote properties where grid connection is unavailable or prohibitively expensive. Cabins, farms, telecom sites.
Pros: Total energy independence. No electricity bills. No grid vulnerability.
Cons: Highest battery cost. Must size for worst-case (cloudy days). No grid backup for extended bad weather.
Hybrid System (Optimal for Most)
Connected to grid but with battery bank. Batteries store solar for self-consumption. Grid provides backup for extended cloudy periods.
Best for: Most residential and commercial applications in areas with reliable grid.
Pros: Lower battery cost than off-grid. Grid provides cheap backup. Best economics.
Cons: Still requires hybrid inverter investment.
Battery Sizing by System Type
- Grid-tied backup: 1 day autonomy (minimum)
- Hybrid: 1–2 days autonomy
- Off-grid: 3–5 days autonomy minimum
CHISEN Battery — 8 factories, 70M kVAh/year. OPzV/OPzS 100-3000Ah. Tel: +86 131 2666 8999 | jack@chisen.cn | www.chisen.cn