Solar panels needed for 1,600 kWh per month
38 panels
of 400 W (14.8 kW) cover 1,600 kWh/month at 4.5 peak sun hours · about $41,481 before the 30% credit at $2.80/W
System size by peak sun hours
| Peak sun hours | System size | 400 W panels | Roof area |
|---|---|---|---|
| 3 h | 22.2 kW | 56 | 1,204 sq ft |
| 3.5 h | 19.0 kW | 48 | 1,032 sq ft |
| 4 h | 16.7 kW | 42 | 903 sq ft |
| 4.5 h | 14.8 kW | 38 | 817 sq ft |
| 5 h | 13.3 kW | 34 | 731 sq ft |
| 5.5 h | 12.1 kW | 31 | 666 sq ft |
| 6 h | 11.1 kW | 28 | 602 sq ft |
kW = monthly kWh ÷ 30 ÷ sun hours ÷ 0.8 (inverter, wiring, soiling and temperature losses). Southwest US ~5.5-6.5 h, Midwest/Northeast ~3.5-4.5 h.
FAQ
How many solar panels for 1,600 kWh a month?
About 38 panels of 400 W (14.8 kW) with 4.5 peak sun hours; 28 in a 6-hour sunny climate and 48 at 3.5 hours.
What does a 14.8 kW system cost?
At a typical $2.50-$3.20 per watt installed: $37,037-$47,407 before incentives.