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How Many kWh Does a 300 W Solar Panel Produce?

Estimate how many kWh solar panels make per year, month and day where you live.

Loads the state's average price per watt, electricity price and solar output. You can edit any of them.
Measure by
kW DC
panels
From NREL PVWatts for your state.
kWh/kW

Your result

Enter your numbers and press the button. Your result appears here.

A 300 W panel is 0.3 kW. Multiply by the yearly output per kW in your area: about 410 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: 0.30 kW makes about 410 kWh a year, 34 a month and 1.1 a day.

At a glance

Same settings as the calculator, changing only the kwh per kw.

kWh per kWPer yearPer monthPer day
1,100330 kWh28 kWh0.9 kWh
1,200360 kWh30 kWh1.0 kWh
1,300390 kWh32 kWh1.1 kWh
1,400420 kWh35 kWh1.2 kWh
1,550465 kWh39 kWh1.3 kWh
1,700510 kWh42 kWh1.4 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/