How Many kWh Does a 400 W Solar Panel Produce?
Estimate how many kWh solar panels make per year, month and day where you live.
Your result
Enter your numbers and press the button. Your result appears here.
A 400 W panel is 0.4 kW. Multiply by the yearly output per kW in your area: about 547 kWh a year at the U.S. average.
How it works
Yearly kWh = system kW × yearly kWh per kW. Monthly = yearly ÷ 12; daily = yearly ÷ 365.
Example: 0.40 kW makes about 547 kWh a year, 46 a month and 1.5 a day.
At a glance
Same settings as the calculator, changing only the kwh per kw.
| kWh per kW | Per year | Per month | Per day |
|---|---|---|---|
| 1,100 | 440 kWh | 37 kWh | 1.2 kWh |
| 1,200 | 480 kWh | 40 kWh | 1.3 kWh |
| 1,300 | 520 kWh | 43 kWh | 1.4 kWh |
| 1,400 | 560 kWh | 47 kWh | 1.5 kWh |
| 1,550 | 620 kWh | 52 kWh | 1.7 kWh |
| 1,700 | 680 kWh | 57 kWh | 1.9 kWh |
Common questions
How much electricity does a solar panel produce?
A 400 W panel makes about 550 kWh a year, or 1.5 kWh a day, at the U.S. average of 1,367 kWh per kW. In Arizona it is closer to 700 kWh a year.
Why is my output lower in winter?
Shorter days, a lower sun and snow cut production. The yearly figure averages the seasons.
Sources
- NREL PVWatts v8 (20° tilt, south-facing, 14% losses), state results compiled by TheGreenWatt: https://thegreenwatt.com/average-peak-sun-hours-by-state/
- NREL PVWatts Calculator: https://pvwatts.nrel.gov/