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roof space

Solar Panels

How Much Roof Space Do You Need for Solar Panels?

Each 400W solar panel needs about 21 square feet (2 m²) of roof. See how much space 5, 8, 10 and 15 kW systems need, how setbacks reduce usable area, and what to do if your roof is too small.

October 2, 2026 · 5 min read

Appliance Wattage Guide

  • Refrigerator 150W (1.5 kWh/day)
  • 5,000 BTU Window AC 450W – 500W
  • Starlink Satellite 50W – 75W
  • Microwave Oven 1,000W – 1,500W
  • CPAP Machine 40W – 60W
  • 1/2 HP Water Well Pump 800W – 1,000W

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Calculations provided for preliminary planning purposes only. Always consult a licensed electrician.