How Do Solar Panels Work

How Do Solar Panels Work — sizing rules, panel counts, battery/inverter picks, and calculators for real‑world use.

Size my panels Battery runtime

{h1}

Quick estimate

Step 1: Watts × hours = Wh/day. Step 2: Divide by peak sun hours, then account for 15–25% losses.

Use these tools

Worked example

120 W × 8 h = 960 Wh/day. With 5 PSH and 20% losses: 960 ÷ (5×1000×0.8) ≈ 240 W array. Choose 300–400 W for headroom.

Tips

  • Pure‑sine inverters for compressors/electronics.
  • Batteries ≥1.5× daily Wh.
  • Keep panels clean/angled; watch cable losses.