How Many Solar Panels Do You Need? A Simple Sizing Guide
Determining the number of solar panels for your home, RV, or van shouldn’t involve guesswork. If you buy too many, you’ve wasted money; buy too few, and your batteries will never reach a full charge. This guide provides the exact formula to calculate your solar array based on your specific energy consumption.
Step 1: The Three-Variable Formula
To find your total panel count, you need three numbers: your **Daily Watt-Hour usage**, the **average Peak Sun Hours** in your area, and the **wattage of the panels** you plan to buy.
Example: If you use 2,000Wh per day and live in an area with 5 Peak Sun Hours, you need 400W of solar. If using 100W panels, that is 4 panels total.
Common Solar Array Benchmarks
| Setup Type | Daily Wh Goal | Recommended Array Size |
|---|---|---|
| Weekend Camper | 300Wh – 500Wh | 100W – 200W |
| Full-Time VanLife | 1,200Wh – 2,000Wh | 400W – 600W |
| Off-Grid Cabin | 4,000Wh – 6,000Wh | 1,200W – 2,000W |
| Standard Home | 25,000Wh – 30,000Wh | 6,000W – 10,000W |
Hardware & Scaling Tips
When selecting panels, bigger isn’t always better for portable systems. 100W panels are easier to mount on curved roofs, while 400W residential panels offer the best “dollars-per-watt” for fixed structures.
- 🛒
100W Monocrystalline Panels: The standard for modular DIY growth.
- 🛒
Z-Bracket Mounts: Essential for ensuring airflow under the panels.
- 🛒
MPPT Charge Controller: Necessary to convert all that panel power into battery storage efficiently.
Solar Sizing FAQ
