Solar energy in Washington, D.C., United States

Average irradiation 4.12 kWh/m²/day · ~1203 kWh per kWp per year

4.12
Avg GHI (kWh/m²/day)
1,203
kWh / kWp / year
6,000
kWh/yr from 5 kW system
38.90, -77.04
Coordinates

Monthly solar irradiation & temperature in Washington, D.C. (NASA POWER)

MonthIrradiation (kWh/m²/day)Avg temp (°C)Est. production per kWp (kWh)
Jan2.170.153
Feb2.971.372
Mar3.975.897
Apr5.0012.2122
May5.5717.6136
Jun6.2022.8151
Jul6.0425.8147
Aug5.3625.1130
Sep4.3921.3107
Oct3.3214.481
Nov2.477.860
Dec1.912.846

Solar potential of Washington, D.C. explained

Washington, D.C. receives an average of 4.12 kilowatt-hours of solar energy per square metre per day, measured over four decades of satellite observation. In practical terms, every kilowatt-peak of installed PV capacity yields about 1203 kWh of electricity per year here, assuming a well-oriented system with a typical 80% performance ratio. This is a solid mid-range solar resource: production is meaningful year-round, though winter output drops noticeably.

Frequently asked questions

Is solar worth it in Washington, D.C.?

With 4.12 kWh/m²/day of average irradiation, a 1 kWp system in Washington, D.C. produces roughly 1203 kWh per year. That is a good solar resource; with current panel prices most systems pay back well within their lifetime.

How much electricity would a 5 kW system produce in Washington, D.C.?

Approximately 6,000 kWh per year — enough to cover a large share of a typical household's consumption.

What data is this based on?

Long-term satellite observations from NASA POWER (1981–present) and the PVGIS SARAH3 database, assuming a performance ratio of 80%.