You don't need a whole-home solar system to survive an extended emergency. This guide shows the 400W–1kW minimum viable solar setup that keeps your critical loads running for minimal cost.
When the grid goes down for an extended period, what do you actually need? Most families can meet their critical needs with a surprisingly modest solar setup:
These critical loads total 500–1,500 Wh/day for most families — achievable with a 400–800W solar system and a 2–5 kWh battery bank.
| Component | Spec | Cost |
|---|---|---|
| 2 × 400W solar panels | 800W array, portable or mounted | $240–320 |
| 30A MPPT charge controller | EPEver or Renogy | $60–90 |
| 100Ah LiFePO4 battery (24V) | 2.4 kWh total / ~2 kWh usable | $250–400 |
| 2,000W pure sine inverter | Handles refrigerator start surge | $150–250 |
| Wire, fuses, connectors | Complete wiring kit | $60–100 |
| Enclosure/mounting | Basic weatherproof box | $50–100 |
| Total | $810–1,260 |
This system provides 2 kWh of usable storage (topped up daily by 800W of solar) — enough to run a refrigerator, lighting, and device charging indefinitely in any location with 3+ peak sun hours per day.
A portable system — panels that fold up, battery that rolls around — offers advantages in a survival scenario:
The tradeoff: portable panels are less efficient per dollar and more prone to damage. For a permanent location, fixed mounting is more cost-effective.
Water security is more important than any other load in a survival scenario. Your solar system needs to address it:
Information and communication are survival-critical. Prioritize these low-power devices:
Total communications + lighting load: 50–100W continuous, 300–500 Wh/day — tiny compared to refrigeration. Your survival solar system handles this easily.