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Choosing between Off-Grid, Backup and Hybrid
Calculation4 min readUpdated: 2025-06
| Plan | Grid | Battery | Best for |
|---|---|---|---|
| Off-Grid | Not used | Everything (day + night) | Remote sites, no grid |
| Backup | Primary source | Outages only | Frequent blackouts + cheap grid |
| Hybrid | Last resort | Nights + 1 day autonomy | Savings + independence + blackout protection |
The key parameter for choosing between Backup and Hybrid is the number of outage hours per day. With less than 4h/day, Backup is often more cost-effective. Beyond 8h/day, Hybrid or Off-Grid is the right choice.
In Backup mode, SolarDim Pro sizes no solar panels — the grid is the only energy source. In Hybrid mode, panels cover daytime consumption and batteries take over at night.
Common mistakes
- Choosing Off-Grid when a reliable grid with few outages is available
- Choosing Backup for a site with 10h+ of daily outages (Hybrid would fit better)
- Not asking for the real number of outage hours before choosing the plan