Comprehensive Guide to Emergency Solar Power

Solar energy is the only infinite power source available to the average person. In a long-term crisis (SHTF), when fuel runs out, solar panels will be worth their weight in gold. They allow charging radios, flashlights, and even powering fridges or power tools.

1 Types of Solar Panels

Monocrystalline

Most efficient (15-22%), black, space-saving. Best choice for permanent installations and RVs.

Polycrystalline

Cheaper, blue, slightly less efficient. Good if you have plenty of space and a limited budget.

Flexible / Foldable

Ideal for backpacks (hiking, bugging out). Lighter, but less durable and more expensive per watt.

2 System Components

Charge Controller (The Heart)

PWM (Pulse Width Modulation)

Cheap, simple, but inefficient. "Clips" panel voltage to battery voltage, wasting excess power. Good for small, cheap systems.

MPPT (Maximum Power Point Tracking)

More expensive, but recovers up to 30% more energy by converting excess voltage into current. Essential for serious setups and cloudy days.

Inverter

Pure Sine Wave

Necessary for motors (fridges, pumps), audio electronics, and medical equipment. Provides grid-quality power.

Modified Sine Wave

Cheaper. Suitable for heaters, light bulbs, and simple switching power supplies. May damage sensitive electronics.

3 How to calculate needs?

  • 1. Sum up device wattage (Watts). E.g., Laptop (60W) + Bulb (10W) = 70W.
  • 2. Multiply by usage time (Hours). 70W * 4h = 280Wh (Watt-hours).
  • 3. Size the battery. 280Wh / 12V = 23Ah. Add buffer (don't discharge to zero!). You need min. 40-50Ah.
  • 4. Size the panel. To charge 280Wh in 4 sun hours: 280Wh / 4h = 70W. Account for losses (panels rarely give 100%). Buy a 100W-120W panel.